I'm new here, but welcome to the boards. You have come to the right place because everyone here is very kind, and full of a wealth of useful information and support!
My first appointment with the pm doctor consisted of lots of questions regarding my medical history, lots of questions regarding the injuries/surgeries that caused my chronic and long term pain, and a general physical. My doctor had the records from my referring doctor several days prior to the first appointment, so he had already familiarized himself with most of my information. Unfortunately, my first appointment was also somewhat rushed as he had to leave town and therefore, had to get out of the office early.
I also had to fill out quite a bit of paperwork, so try and get there about 15 minutes early. I had to read and sign a list of the rules my doctor requires and had to sign a contract regarding controled substances/opiates. I am only able to get medications at one pharmacy and am not allowed to get prescriptions for narcotics from any other doctor for any reason.
I would highly recommend writing down and questions and concerns you have regarding your condition and what sorts of treatment options your doctor offers. This will help to avoid you forgetting anything important. Make a copy for you and a copy for your doctor. You can jot down notes and the doctors answers on your copy. It also helps to have any x-rays, MRI's and CT scans with you if your referring doctor did not send them a copy. The more background the pm doctor has, the better equipped he will be in finding the right treatment options to suit your needs.
Of course, all doctors and pain clinics have their own rules and their own way of doing things. Some rely on more "alternative" treatments, while others use a good combination of "alternative" as well as medication style treatment. They will probably be very specific with the requirements.
I am glad you were able to get an appointment with a pm doctor. Living with long term, chronic pain can be such an exhausting and debilitating experience. Please let us know how the appointment goes!