Well, maybe your mind is racing when you're trying to sleep. For example, if i am running around and doing stuff or on the computer and try to go to sleep RIGHT after i get done doing what i'm doing it doesn't work.
Maybe what you could do is get a tv in your room and lay down at least an hour before you want to go to sleep and watch your favorite show for an hour or more and then try and go to sleep. Your mind will not be racing anymore, and try to not think about much when trying to sleep.