Growing pains?!? (Sorry)
Alright, I recommend you try to find a spe******t that is trained in this field (Doctors are good to) but try to look things on the internet the things that you have listed here on Yahoo Answers! and kind of get more aware of what is happening to your son (Don't believe in everything you read) then go and speak to your doctor then he.she and you along with your son can try to figure out what is happening with you son Cat scans don't always pick-up things sometimes machines can miss things here and there like everything in today's world has its positive and negative effects.
I hope this helps and Good Luck
It may be mini strokes or seizures that your son is experiencing.