He never even liked me so why do I feel like this?

I’ve had a huge crush on this guy all year. He would stare at me, but then look away really fast when I saw him. He could never speak to me and the few times that he did he looked at the ground or the wall. His friends even the ones I don’t know started acting weird around me. If I walked by them they would tell him and he would look at me and turn away really fast. If I was with his group of friends he would stay off to the side and wait until I left. He would do some other similar things. I never told anyone that I liked him so he didn’t know. I took these as signs that he liked me. I’m really shy and I was even worse around him. I kept hoping that one day he would ask me out. Everyday in class I thought it would be the day. I tried to bring myself to say something, but I couldn’t. Then on the last day of school he never said anything. I felt like crying. I couldn’t even look at him in the halls. Now I can’t stop thinking about him and to make it worse it seems every time I watch TV or do something there is a guy with the same name. I’ve had crushes on guys and the school year ended with nothing happening and I never felt like this. Obviously he didn’t like me or I think he would have done something so I don’t know why I let it bother me. Why do I feel like this? How do I stop feeling like this?