Is the counselor a psychologist or something less than that? It sounds like he's very depressed, but to get a proper diagnosis and therefore proper medication he needs to be seeing someone who has the credentials to do that. And if he's still this bad off and has been on the Prozac for awhile, it's not the right med for him as it's clearly not working.
Is it possible your son is confused about his sexual orientation ? I say this because a teen I parented in foster care had similar behaviours and this was eventually found to be the cause of his distress.