Is he playing hard to get :(

So there’s this boy I like & i hate liking people because im not the prettiest girl & most dont like me back but we would talk almost everyday because I check out a book for him because he can’t at that time I didn’t like him but now I do. So yeah that’s the only reason why we talk he would come up to me at lunch and say he would bring the book but he would never until it was actually due then he would sit next to me at lunch because his friends ditched him and we would just talk about other random things. And it was all good until now. He’s really nice to me which I just don’t understand anymore because he started to ignore me but at first I just though he had a bad day then the next day he would talk to me & sit next to me with his friend & talk to me we’d play flappy bird to see who’s better & stuff like that. & after school we had to go to a class to take a test & I sat next to him. Then he like would touch my bag randomly & he sprayed Cologne ( why’d he do that? ) and askes me questions like whats my dads name & I asked why and he said because his dad asked. So do you think he talks about me? & he keeps on telling me the same things does he just want to talk to me? but Then the next day he ignored me like the other day before. It just looks like he doesn’t know me like if I don’t exist. Why does he do this?? Is he bipolar or something? And in 7th he came and talked to me asking me my dads name I guess he’s just making sure we aren’t related because we both have the same last name which is weird. So Monday he ignored me so I thought he would talk to me today i was happy today that he would talk to me. He didnt. He just looked at me. What should I do? Should I talk to him. I feel so sad I just knew I’d get hurt <\3. I’m confused did I do something wrong?