Hi, one thing to ask about with your developmental pediatrition is sensory related issues. Very often sensory issues are comorbid with autism. My autistic nephew has many issues attributed to his overlapping sensory.
And I have a son with sensory integration disorder (which a person can have all on their own as well.). Some kids with sensory have wrong signals sent via the nervous system. This can include pain as well. My son had reactions to things that made no sense such as water getting on his hands. He acted like this hurt and for him, it did. His nervous system was oversensitive and sending that message to the brain. My son is also a mixed bag------ he has oversensitivity to pain so a minor bump becomes a major issue he fixates on and then he has undersensitivity in that he can do things that look like they'd send the average child to the emergency room and he comes out smiling from it. (He's a sensory seeker, so he looks for direct contact input into the nervous system.) Actually, it is quite dangerous for kis that are undersensitive to pain and you can imagine why. They can have horrible injuries that do not get treated. Anyway, this is something to talk to your developmental doc about.
We do occupational therapy which helps tremendously. They work directly on the nervous system to help get it regulated to send the right messages. We've had really fantastic results. There are kids all over the spectrum at the institute that we go to as their specialty is sensory. So, check around and ask questions if you are indeed going to add occupational therapy to your list of services. By the way, ot's make their sessions like fun play dates. I've overheard my kid telling his friend "Oh, you should really go to therapy. It is so fun. Maybe I'll take you with me sometime!" LOL You gotta love that.
Or perhaps with toe walking, etc. he's hurting himself. They do often check things like flexibility with my son and core strength as it plays into things a bit.
So, there are a lot of things that could be going on. I hope you find some answers. If you need any ideas related to sensory, let me know! good luck
It wont get any better for waiting its better to just do it, or you will still be concerned about it , it does sound like growing pains but always best to get a diagnosis.I am wondering if there are some exercises you can do with him, so he is copying you, rather than standing or sitting for long periods you may want to ask the Doctor about that. Have you asked any other parent on the Autism forum there may be some ideas there.. Good luck