Does my son have Asperger's Syndrome?

My son (13 1/2) had been diagnosed with ADHD but it feels like as he gets older; it's more Asperger's Syndrome.  He is extremely antisocial, has difficulty controlling his emotions, does not make eye contact EVER when spoken to and is struggling to fit in!  I have always said that this one (youngest of 3) "beats to a different drummer" but now I'm afraid that the drummer is Asperger's!  He had an extreme emotional breakdown last night to the point where I considered hauling him off for a psychiatric evaluation... I'm exhausted!  He is exhausted and says he "doesn't want to talk about it" or that "he doesn't know" when I ask him what is going on.  He is getting D's & F's in school yet he can spend 10-15 hours a day on his video games - he has ALWAYS struggled with reading and anything to do with language but has done very well in math.  He was receiving state funded help in elementary school but last year (7th grade) "tested out" of this added educational support.  I am wanting to get him help but I'm not sure which direction to go in.  I have an emergency appointment with his ADAD doctor/ped. tomorrow along with a request for an adolescent mental health therapist... please let me know your initial thoughts.