I was diagnosed with intractable migraines so I get the pain with them. But, over the last 6 months or so, I've been getting worse. I get extremely dizzy, nearly fainting. I get nauseous and feel really sick. I get no pain during these episodes. I thought maybe my tumor was back but a scan ruled that out. My PCP put me on Meclizine for vertigo but it didn't help. I did a little research and I have the symptoms of the same ailment your son suffers from. I have yet to get an actual diagnosis but everything else was ruled out.