Before you have your son tested (and spend the money on it, as it can be very expensive) you should ask the school what if anything they would do with the test results of that particular test. When we talked to our DS's school today, they told us we could implement a learning planning without having any test scores (that saved us $500).
My DS is a talker and a singer and generally very "fidgety", but he does not have ADD or ADHD or the like. We have found with him that having something to channel his energy into, aside from talking is helpful. Chewing gum or fingering a coin we have found to be very helpful in times of "excessive" talking when it is not called for.
