Being ill at really inappropriate times. And sleeping a lot, when you're used to being able to stay up late with very little in the way of ill effects.
/whine
Er... I should say something else so this isn't just the Grumpy Ill Post that I'll cringe at in a few days. Have a limerick.
There was a woman, name of Narcissa,
Her husband did love to kiss 'er,
The Aurors didn't aim to please,
So she kicked 'em between the knees,
They cried, and all the hexes missed 'er!
...I'm tired.