Why would this guy avoid me?

Well theirs this one guy who (I think) likes me...But he tends to avoid me and (quite literally) run past the class I am in, when ever he is on facebook he goes off instantly when I am on... He has shown interest however by constantly staring at me, blushing, constantly preening himself, touching his lips, wearing aftershave (he only started when I would say the signs started ) and he constantly smiles at me... - This is only in class though so why would he avoid me after? I have noticed that he becomes very, very shy around me as well when he is naturally very outgoing... I really like him so why would he avoid me? I asked weather he likes me online and he replied with "in what way" but didn't tell me if he did or not please help I am confused :(