Table Trouble

I'm beginning to suspect AJ doesn't like crowds or a lot of noise. He is very similar to me in that.
Usually, we drop him off at school so early that there aren't really very many kids there yet. It's pretty laid back and he picks out a table and goes to sit down by himself.
On the occasional days that he gets dropped off a little later, the reaction is quite different. Those are the days when he looks around at all of the occupied tables, listens to the other children talking/yelling, and gets clingy. He won't pick out a seat, even at the table where his own classmates are sitting. He doesn't mind sharing the table, but he needs to be the first one there. It's like he needs everyone to come to him. I don't know if he's overwhelmed or just needs everything to revolve around him?
Thoughts?