Hi there and welcome to the board.
I totally suggest taking him to a neuropsychologist for a complete evaluation so you know what you really are dealing with. While nothing is 100% accurate, since there are no blood tests, there are tests that NeuroPsychs do that can indicate certain disorders/problems/deficits/strengths/things to build on. My son had ten hours of testing and finally got the right diagnosis from a neuropsychologist. Many of us are very happy with their method of evaluation, which is different than a pediatrician (they usually don't know), school (ditto), therapists (not really trained to diagnose), and in my case and opinion even psychiatrists don't usually test enough. I have psychiatric disorders myself and have seen ALL types of professionals and this is my opinion on how to best figure out what is going on.
If you want to help us help you more, we need to know more. How was this child's early development as far as eye contact, speech, cuddling, ability to relate to strangers and same age peers (this is as he grew), motor skills, school performance? Can he transition from one activity to another without a meltdown? How is his ability to hold a give-and-talk conversation?
Are there any psychiatric disorders, either diagnosed or suspected, on either side of his genetic family tree? Any substance abuse, which often points to somebody who has an undiagnosed mood disorder? Any autism in the family? Aspergers?
Others will come along. You may want to do a signature like I did below. It will help us remember you.