How to tell if a guy is thinking about you when he's alone?

OK this guy has made it very clear that he is indeed attracted to me. We started talking and then one day he stops, he just stares and smiles. So then I thought 'oh well it was nice while it lasted' then his friend comes around me and starts laughing, when I ask him what the hell is so funny he says 'i can't tell you' he finally told me after I gave him back his hair that he (the guy I like) told him that he had a dream about me. And that he (my crush) thinks about me..daily. Now my question is how can I tell? his friend could be lying. can I get my crush to talk to me again, like old times :}