Whys he doing this? Advice needed please! :|?

Last year me and this guy have became really close friends. Then i started to like him as more than just a friend but didn't say nothing because i was scared of rejection. Then towards the end of the summer term he started calling my name and when i would turn around he would wink, he started stoping me about 4 times a day just to give me a hug and then whispers in my ear that he missed me, he sat next to me in all the cles we had together and when we went on a school trip we had to go in groups and he was resting his hand on my knee for the whole activity. I don't know if any of them were signs that he liked me but i was sort of getting my hope up. We are still really close but now he doesn't do any of that. I was in cl the other day and i was talking to his mate and one of the girls in my cl said "Oh you would make a nice couple" I just laughed and so did the guy cause hes like a brother. But then i turned around and the guy i like looked at me then looked down and smiled. Today in cl i had to sit next to the guy i like and we were having a laugh and one of the boys said messing around "Oi dude stop flirting" and another guy said "nah leave them to it, it's about time they get it on" the guy i like just looked at me and smiled and i smiled back. And now he starting to like flirt with me again. It's as if he doesn't know if he likes me or not and i don't want to be messed around! Whys he doing this?