((((((((Ambrosa)))))) Ugh. I'm so sorry you're going through this. I can really relate and I know how agonizing it is to live in this cycle of panic attacks. I also get very panicky at the dentist. And I know exactly what you mean about tending to avoid places where you've had a panic attack before.
I agree with onmyway that nighttime is often a bad time for us anxiety sufferers.
I forget whether you've talked about medication? Are you taking anything? I take an anti-depressant and it does help somewhat with my anxiety. I avoid sedatives because I worry about addiction and also because I worry about my heart rate being slowed down too much (since my heart rate is naturally on the slow side).
Anyhow, while your anxiety and panic is so acute I think that medication could be helpful. So I'm hoping this is an option for you? I know you're in the process of changing doctors, but hopefully you can talk to someone about medication options soon?
Many hugs to you