Big hug. The good news is, you have a good Dr who is alert to these things, and, the earlier you can start to get therapy for your child, the better chance you will have of helping making him more comfortable- OT, physical therapy, speech, he may be young for ABA. OT will help improve his muscles and coordination. Ask everyone you can find who has experience with this for advice. Contact local autism groups. And trust your instincts on what is best for your child. You will say yes to some things and no to others.