On Negi's general feelings as a whole, his reaction to the Wolf game, his feelings after getting bit in the dream world and getting chewed out, and why he might reveal to his castmates soon.
This is ridiculously long and kind of includes a sum-up of just wtf all happened, too.
Some things to understand off the bat - firstly, Negi is smart. After all, you've got to be in order to be a tiny ten-year-old teacher. But it's the sort of smart that only encompasses a tiny, tiny dash of common sense, and a very great deal of second guessing himself. For Negi to be actively certain of a path to take typically requires either a very long period of soulsearching combined with a discussion with at least one member of his extended contacts network, or else a sudden and deeply pressing need to act right the fuck now with all haste. Without either reassurance or urgency he's a ditherer, and will dither all day if given the chance. Secondly, he's a naturally lonely, quiet sort. For years he's lived and studied on his own after some serious backstory catastrophes, just chilling and very occasionally getting kicked in the head by Anya for his own good. But then he's thrown bodily into Mahora and meets and suddenly has to chaperone an entire class of young girls where, at heart, none of them dislike him and all are generally well-disposed towards him. And he's fawned over and adopted and then abused and flung into the bath and normal life ensues and Negi reaches some semblance of normalcy and ... maybe still remains a little confused at all of this, but really really likes the sudden day-by-day dealing of life. He's literally indebted to his students, not just because he's their teacher and feels a great responsibility there but also because he would, earnestly and without hesitation, count every last one as a dear friend.
(For those who haven't been keeping count at home: Of castmates, Ayaka, Chizu-nee and Misa do not know about Negi's mageliness. Yue, Haruna, Chisame, Mana, Kotarou and Setsuna do.)
So! Negi's been poking around camp and chilling and starting to realise that well, maybe they weren't kidding about their being no easy way out of camp as all his research leads dry up, so what now? ... and then Chizu-nee falls out of a magical portal along with a guy in a coma.
Not only is this big news, but for Negi it is kind of terrifying news. He doesn't like any of the no-know people getting seriously mixed up with magic, for a combination of reasons: first, it means they learn about magic and can get more suspicious more easily, leading directly to a more difficult-to-maintain cover. Mahora's crazy, man, enough weirdshit happens there daily to flag anyone's magic-o-meter and it's often a very rocky balance they're working with to keep magely identities secret. A brief bit of knowledge about magic could colour the festival arc events in enough of a new light to give him away. Second, it's a kind of possessiveness and protectiveness on his part as regards his students, mixed with a dash of selfishness - don't subject them to magic, they don't know yet, it's not fair. If it were someone who knew he was a mage getting attacked he can be more free with his information and thoughts, but with no-knows he's just a kid who happens to be their teacher.
So he has to be careful. Something's happened, but he barely knows what. He tiptoes around the issue with Chizu-nee herself, understanding she doesn't want him involved; he asks about the first time she was anywhere near magic, just to try to test her suspicions. He finds out from other sources about the game, and accidentally brings it up with her to receive a rather frosty response, and promises not to do anything too dangerous. (He also, in retrospect, makes a truly terrifying promise that to make her feel better Chizuru can freely order him around some, which may kind of spell his doom given ensuing events.)
It's worth noting at this point that, uhm, if Negi ever says 'I won't do anything too dangerous' this is a Trap and you should be very wary of it. Negi will do a very great deal for the people he likes and easily gets caught up in events and that suddenly makes 'too dangerous' a very, very small band indeed. So he checks Cloud over for magic, goes into his head using a spell to poke sleeping people's memories... and gets bitten and knocked out of it quite forcefully, just about realising that this man, whoever he is, has traded for Chizu-nee. This makes him Very Important because Negi is exactly the sort of person to pay his debts and take them deadly seriously, especially where matters like saving his students are concerned. Cloud has Done Good and he kind of automatically gets a free pass to know what's going on because of that.
He further sneaks around Chizuru to get more information and with an aim to attempting to contact the dreamworld and try to find out what's going on there. This truly isn't done out of malice or a desire to leave her out of the proceedings, per se - rather, he justifies it completely to himself in his ten-year-old way by saying that now that she's out she shouldn't go anywhere near it, and that he's sparing her feelings and repaying his debts and Doing What He Can To Help, especially when Morrolan, the defacto leader of the wolf resistance and hotshit wizard, states that he can't do dream-hopping magic. This has not just become Something Negi Can To, but Something Apparently Only Negi Can Do. Negi likes being useful, it's a definite character trait borne of kind of neurotic responsibility issues.
He goes in there, has a look around, faces the wolf. Wolf beats the snot out of him - though Negi manages to land his own punches, too - and Negi is kicked out of the dreamworld with quite a bit of blood loss and some awesome cuts and scrapes and not a few holes in his shoulder, not to mention a distinct need for a new tiny suit. But... he found something like a clue, and that was exactly what he went in there to find and to Negi finding that and getting out was a perfect, 100% success. No bonus goals were achieved - he didn't kill the wolf, for instance, nor did the ringmaster answer any of his questions - but he accomplished exactly what he set out to do, which was to learn more and maybe find a weak point in the ringmaster's armor and get out alive.
And then Chizu-nee finds him as he bounces off a wall--
This has nothing to do with this essay but okay one thing I learnt from Wolf is that bouncing Negi off walls is somehow hilarious
--and in his excitement and haste and general beat up state he basically runs through exactly what he's been up to and what he's found. He stops just short of saying he's a wizard, but he otherwise admits that he's been in a dreamworld and has found a hole in there and that maybe some people can be led in there to take on the ringmaster at his own game. It's out of left field for Chizu-nee probably but to Negi, well, he's sitting there bloody and torn up in the middle of a hospital across from a coma patient, what exactly can you say that'll be believable? And then Chizuru and Faust both get on his case about how it's not appropriate for a ten-year-old to be throwing his life away, and that's where he breaks and actually gets angry.
To Negi, he wasn't throwing his life away, certainly not intentionally. For one, he didn't know if the wolf would even be there - he was intending to take a look and then leave. The wolf did show, yes, but Negi escaped alive and that's all that really matters to him - he doesn't particularly register 'wounded' on his mental scale of states. 'Negi is okay' -> 'Negi is dead' pretty much sums it up, as he's the sort to constantly barrel on and on even after injury and injury and in fact works better in those situations as time goes on. More importantly, though, is this thing where he's not just a ten-year-old. He's a ten-year-old mage who had Something Only He Can Do and decided to act after checking with his castmates - he's a ten-year-old teacher who takes his duties very seriously and who will desperately do whatever he can for his students - he's a ten-year-old who is typically in a living situation where age roles are reversed - or at least really screwed up sideways - until he doesn't even register them anymore. He sees himself as perfectly justified - regardless of what could have happened, he's alive and won and what else matters in his tiny ten-year-old black-and-white brain?
He's upset, in short. Not specifically at either Chizu-nee or Faust as he realises on some level that they're just concerned - he'll be sulky at them, but that will fade certainly in Chizu-nee's case as concern for how she's doing takes over. (Faust's sulk will fade too, but notably slower - for one, he's not a Student and for two, he knew openly about Negi's mageliness and so Negi cannot as easily understand why he might be upset at Negi's actions.) Most notably, thanks to the events of wolf, he is nearing a definite point where he wants to reveal himself to his castmates and do away with the whole mage-secrecy thing.
Firstly and most obviously, he just doesn't like lying. He's not a good liar, not even an acceptable one, and it makes him feel guilty that he's had to do so for so long. The whole mage secrecy thing barely seems even to count in camp, where extraordinary circumstances make magic and mundane mingle and mix more-or-less most months, (fuck yeah, alliteration) and he doesn't like being the only one in camp with this cross of silence to bear. There is also a ten-year-old element of boasting in there, and he can't deny that he'd like to be able to show-off and just cut loose more often. Far more importantly, with camp getting more dangerous and it culminating in what was practically a Halloween in February, Negi feels strongly that he's holding back and not doing his part to help out. Sod being tiny - he wants to help and feels he could help if only people would understand that he's not just an average ten-year-old. They're in an enclosed space and there is only so much help available and it is typically important in that situation that all cards are placed fairly and squarely on the table. Even in the current magic world arc, we can see this: stranded as they are it is very, very little time before most of the mundane class that came with them learn about Negi's powers with the only exception being the girl who just isn't mentally strong enough to take the news.
So Negi wants to reveal. He doesn't... expect to catch much hell for this - Yue and Setsuna will likely weigh benefits and drawbacks carefully and tell him to be bloody cautious but leave the final choice up to him, Mana and Kotarou won't care (but both of them will grin when they say that), Haruna will think it's hilarious. Chisame is the only real 'problem' in Negi's mind - the one most likely to raise a series of solid objections and expect him to come up with solutions for them. (Yue would raise objections but probably be content to leave them hanging as suggestions; Chisame would want answers, damn it.) This is fine, because Chisame is also... the strategist, and canonically is the person who is typically most ready to knock Negi down a few pegs. He expects that, it's cool, and while he might not have anything in the way of answers for her... he'll probably go do it anyway, because that's what he does when he's finally got an idea in his head.