I think a boy likes me

I have a best friend. I'm a girl, and he's a boy. We've been friends since we were 7. I don't know how, but at some point we started kissing each other on the cheek as a sign of affection. It never bothered me. I told him everything; we were very close, and he was there through thick and thin. When I was 14 I started to have feelings for him during the summer holidays and since I was a coward I confessed by text message. He told me he didn't like me that way, and I accepted it. Then I realized he was right. I saw him more as a brother than a boyfriend 

After what happened, I never felt much for him until he started having weird approaches, giving me kisses all over my face, hugging me too much, defending me from people who bothered me. Etc. 

It really seemed strange to me but I tried to ignore it but he continued with the same thing, at some point we were both walking and he saw that my friends were holding hands with their partners. Then he took my hand and said "look there are 3 couples here" and I said "there are only two" And he changed the subject, I just decided not to pay attention to him. 

Another day we were talking and I said that I really liked chubby boys and that I couldn't be with a boy who wasn't like that (he's too thin because he has trouble gaining weight) Then he got defensive and started hugging me and kissing me more insistently. 

I think he's in love with me, but I don't know how to tell him that we're not the same because every time I try to avoid it, he says, "Why are you acting like this? We're just friends, we always have been." 

Sometimes I don't know if he likes me or not because I'm autistic and can't fully relate to that kind of thing. Do you think he likes me?