What tests/tester to sort out Aspergers,Gifted,Anxiety,SPD, ADHD?

I have a 4 year old that is just wired a little differently. It's starting to be a problem at preschool with rigidness, social situations, Sensory issues. What kind of tester and what kind of tests should I look for to sort out and find the root of these problems? I don't even know where to start. My ped told me my son is just spoiled and that's why he vomits things like jello, and refuses cotton candy. I don't want to go back there for advice. Where and with whom do I begin?

Last edited by Pranava; 10/30/13 06:22 PM.