What is this boy doing to me?

I liked this senior boy at my high school for about one and a half years. And I think that he liked me back because he gave me a picture of him making one of those weird faces when they see a hot girl ping by. I should mention that he is shy when it comes to girls he likes. The only time I have talked to him was last year November when we went to kmc. But it wasn't really a long conversation, i asked him a yes or no question and he just said yes he was killing us. (we were playing games in our band) Then in december, before christmas break during our last day of school embly, I asked my boy friend to ask him out for me cause I couldn't stand it anymore. My friend knows him cause of they go to the same church. I figured if he said no, i'd have two weeks to get over it. And guess what happened.... he said no. So now i'm kind of mad at him because he gave me his picture for what reason i don't know and then he says no. Then again he might have gotten over me. So i decided to give back his picture he gave to me. So I put it in his folder for band papers (folded) during recess. Then i don't go to rehearsal two days after. Then now when i see him around in school he has that sad look in his face. But why is he sad for? He is the one who said no to me?