Why does he keep doing this to me?

He either is generally worried and cares about you a lot (in a friendly way) or he likes you, and still worries and cares. If you don't have a crush on him, it might be good, because you just have a really good friend. You definitely need to hang out with him because then you can know for sure. If worst comes to worst and you don't know, ask one of his friends, or even him. Just say "why are you so nice to me?" he will either tell you he likes you, that you are his friend or chicken out and say "i dunno". which in that case means you'll have to look harder. but personally i think he may only like you as a friend.