What should I do about this guy I like?

The first time I ever noticed him, we were in an after school meeting, and he was turned around in his seat (which was facing away from me) and was staring at me. On the same day, we had our first conversation and I was astounded because he said stuff to me that sounded like he asked around about me or payed close attention to me without my knowing. As we got to know each other, I started liking him a lot. He also seemed to like me because of his constant staring and smiling when I would stare back. Also, whenever he would see me flirting with another guy, he would look hurt or annoyed, and if I ignored him he would give me desperate looks as if he were saying “please stop ignoring me”. Finally, after liking him for a few months, I told him that I really liked him and was wondering if he would like to hang out some time. This was his response: “I’m really not looking for a girlfriend right now. I’m really sorry. I hope you are not mad at me for it.” I told him I wasn’t and we had a long drawn conversation about how he felt bad for having to tell girls this and blah blah. In the end he thanked me for understanding, and I thanked him for being so nice about the whole thing. But in all honesty, I’m really disappointed and annoyed. I haven’t talked to him since, because I know I need time away from him to fully get over him. However I still see him at school and try my hardest not to look at him, but when we make eye contact, he gives me this look like he’s upset with me and I’m not entirely sure why. Maybe I’m just reading into things or seeing what I want to see because of how much I like him. Please tell me what these signals mean and how I should go about getting over him. Thanks!