Hey. I understand that it's confusing for you, but I hope you do understand that you are who you are, no matter what diagnosis says, and it doesn't really matter in regards to your identity. You're still you.
Not sure about the whole accomodations thing (where I live that's simply not a thing), but I believe that if your doctor tells you you will receive the same accomodations, that's probably the case.
I had a bit of an opposite situation. I was diagnosed with social anxiety disorder and received therapy for it (which wasn't helpful), and then someone unearthed my old records and found out I was diagnosed with autism as a young child. I was reassesed, and my doctor then agreed that I'm indeed autistic. My therapist's reaction was "Well, that's unfortunate, nothing can be done about you then". Social anxiety and autism can manifest in similar ways, but have different underlying reasons. Good news (for you) is that social anxiety can be treated and helped with therapy and medications, and autism symptoms...well, they can be helped somewhat, but for the most part you just got to roll with it and learn to live with them. Have you been offered any sort of a treatment for your social phobia?
I have never experienced synesthesia, so I can't say much on that matter, but I also did have a term "thought disorder" attached to me, after I suffered brain damage. As far as I know it is not a condition, but a symptom that also has both many forms and many causes.
Can you talk to your new psychiatrist about those new diagnoses?