New PTSD diagnosis and anxiety/panic over appts

Hi,
I was diagnosed the other day with PTSD, Major Depressive Disorder, Generalized Anxiety Disorder and Panic Disorder. I have back to back panic attacks before an appointment at the mental health clinic I'm now going to. I also had a bad panic attack at the initial assessment early last week. So embarrassing! They want me there often to start, 2 times/week for individual and once/week at a group. Has anyone else ever experienced the panic about an appointment, and how did you deal with it if so? I have to go tomorrow for a first meeting with a psychiatrist for meds. I'm beside myself with anxiety and panic. I'm not even sure I can do this. I would really appreciate any suggestions for this that you may have. I'm not a group type of person, but with no insurance, it's a requirement to keep my costs as low as they are at this non profit clinic, so I'm also really stressed about my upcoming first group. I truly don't know at this point if I can go through with any of this with the anxiety and panic about it being so high. Thank you in advance.