I am so sorry you had such a terrible, painful, and exhausting day. I hope you are able to get some sleep (or at least rest) tonight. I am very concerned that the doctor and the PT might be pushing you too much. You are the only one who truly knows your body. I'm worried that by overdoing exercises, you are causing swelling which, in turn reduces your ROM.
I have had a number of PTs over the years who have not understood SC and my history and have ended up causing me more problems and pain. Even the PT I worked with after my hip replacement was pushing me too hard. He wanted to use resistance bands on my operated leg less than a week after my surgery. I said I wouldn't do the exercises with the resistance bands, and he acquiesced.
Please listen to your body and do what feels right to you. There are so few people who have SC and have had joint replacements that there is no way to know if our recoveries should or will follow a usual pattern. As Jo said, if your limited ROM is from scar tissue, they can help that later with MUA if it is necessary. I think right now you need to be resting more and trying to get the swelling down. It sounds to me like your doctor was rushed and may not have reviewed your history as thoroughly as he should have.