Welcome to the forum. I'm an adult with SPD. I'm also autistic, so forgive me if this comes across bluntly.

Personally, I would trust your instinct as a mother and talk to your doctor if you have any concerns. And keep fighting and advocating for your son if you still have serious concerns.

I work in daycare with toddlers. If I saw what you're describing, I would consider talking to the parent about it and suggesting talking to their doctor and/or having a birth to three evaluation, just to be on the safe side.

Maybe there's nothing wrong. It never hurts to ask. I'd lay out the symptoms, their impact on daily life and functioning, and your concerns that it might be SPD. Not all doctors are knowledgeable about SPD. In fact many aren't. So it could take some advocating if things persist to a degree that still concerns you.

It sounds like your son has a wonderful caring mother who will advocate for him if/when the need arises.