Yesssss! I deal with both of those issues and no diagnosis

Ahhh 100% I've been having intermittent joint pain on major joints on both sides of my body for years and years... I also have ASD. Still no answers, it's so frustrating

EDS is a pretty common comorbid issue a lot of autistic people deal with. I have hEDS and primarily features joint hypermobility, GI, and skin issues. Just throwing that out that in case it gives anyone a lead as I only found out I had it when my boyfriend who has it showed me his hands and I was like SAME then did research. Definitely not the only joint issue related though. It sucked not knowing what my problem was before then and it was difficult coping. I hope you guys find out what the source of it is and are able to get help. Joint issues are awful.

Maybe look into hEDS! Hypermobile joints doesn't automatically mean you have it, but it's worth a look. The Eds society website has great info+ diagnostic criteria. Even if you don't have it, it might give you some insight on things. If you have the means possibly look into a physical therapist or different YouTube channels for exercises. Eds doesn't have many treatment options that are very fruitful, but maybe in your search (even if you don't have it) you'll be able to find something that works for you. I wish you luck, friend