[OOM: No one ever thought the Triwizard Tournament would end like this.] It’s not that Luna isn’t happy to see Milliways. (Well, happy is probably an overstatement at the moment, but she’s not unhappy to see Milliways.) It’s just not what she was expecting.
So she is standing still, just inside the door, in rumpled clothes and holding a box of jumbled belongings, looking like she’s not quite sure what to do.
She was really thinking her bed was going to be on the other side of the door. It’s only now starting to hit Luna how tired she is.
At this rate, she might go on standing in the middle of the floor indefinitely. If someone were to shoo her toward a chair, it would be welcome.