Hi, our 6 yr. Old son has started spinning 200+ times a day as he walks, plays, sits, etc. He also has to do things in twos. He use to nod and hum...?

Need more info. Is there a particular issue you are worred about? Many kids without behavioral problems will do repetitive actions or follow patters. Within certain limits this is fine, but if it begins limiting their growth and development you should see a child-care specialist to discuss further.
Kids... Kids do very peculiar and even particular things - this can be completely normal behavior. I assume you are concerned about one of the autism spectrum disorders... There are screening questionnaires available which your pediatrician can utilize. Please speak with them about any of your concerns.