Wow, we have the same issue with DS 9 and Doctor visits, although not to the same extent. He does not have a diagnosis but we are having him evaluated as I strongly believe he has Asperger's, especially after reading Tony Attwood's book and posting here and receiving wonderful feedback.
He has a horrible fear of shots, and will kick the nurses and scream...it's awful. I now understand it better, but it's really tough when you're in the middle of it. What I wanted to tell you is, he had to have bloodwork and a kidney ultrasound done a few months ago (he has bladder issues but that's a whole other story). We had the most wonderful Nurse, who took the time to explain to him every step of the way what she was going to do and why. I couldn't believe my eyes when she talked him into the chair and he sat without being restrained while she took his blood. Mind you, it was after 20 minutes of talking, but she was patient the whole time (more patient that I felt). It was all about answering his questions and giving him facts. I don't know if that helps, but I wanted to throw it out there. Good luck with the new clinic.