Son with severe disability appears to be in pain

24yr old - He is also non verbal and recently he is being vocal day and night as if he is in pain. He has had major surgery circa 2014 onwards to correct scoliosis and also a hip reconstruction. This means he has a lot of metal work in his body. I am tired of trying to explain to our family doctor his symptoms who can only do a referral to a specialist which can take up to two months for an eventual appointment. A previous referral was rejected by the Royal Orthopaedic Hospital Birmingham. I feel helpless and don’t know what else I can do. Since he was transitioned in to adult services, he has more or less been forgotten and has no assigned specialist or follow up appointments to check if the metal in his body is still in place.