How do u kno if a guy really likes you?

Me and this guy are pretty good firends and we have a lot of fun together. At first, he told me that he liked me a few years ago, when we were younger, and he makes up nicknames for me all the time, and he's even asked me to the movies before, but i couldn't tell if it was just as firends or not. At the beginning of the week, I glanced up from my desk and caught him starring at me, when i asked him "what?" he just smiled and looked the other way. He keeps asking things like..."u going to the game tomorrow" and " so is there a dance on saterday?". ( you would think that this would hint he likes me) But then all of a sudden he stopped doing all of this. and On IM, he doesnt say more then two words, before he logs off without saying bye. Does he Like me or not?