feeling pain

I have unbearable tummy pains with having IBS and gallstone pain and then there's the good old faithful pain of arthritis and not forgetting the ever faithful fibromyalgia pain. I'm just wondering how do people with ADHD and Autism feel pain. I've heard that people are more sensitive to pain if they have ADHD and  Autism. I'm just wondering if this is why i am in so much pain with having ADHD and Autisms and i can also tolerate a lot of pain as well. I've learnt to block pain out when i can and when i'm unable to for whatever reason the pain is intolerable. It drives me to wanting to take drugs to escape it all or take myself back home. Or self medicate buying medications of the net. It makes my depression and anxiety much worse as well going through unbearable pain.