You are doing everything right, but it sounds like you could use some help too. I would consider having him checked by a psychologist (because that's who gives tests). He can make referrals to psychiatrists or therapists if he thinks that's necessary.

My son has mild Aspergers; when he was little there was no one out there who could help. (This was well before the deluge of autism material) We had him checked by an incompetent psychologist:who had no clue. So no help there, since we couldn't afford testing by another psychologist.

I had to do what you are doing, ie make things up as I went along.Your son is lucky to have you for a mom.