I'm so sorry you have had such a rough go of it lately. My god, it sounds like things have really gotten to the point that you did need to get help, and I am proud of you for making an appointment to see a doctor. It also sounds like you have a good friend which is comforting.
Yes, it's true that hospital is the last resort and I can almost gaurentee you that you aren't going to end up there.
Anxiety is treatable and manageable- even severe cases like mine or yours.
As for what to do about the appointment with the doc? I would start now to jot down a few things...kinda like an outline of things to say. Typically what brings on your anxiety or panic attacks, how often episodes last, how long has it been going on, how long since it has gotten so much worse, how it has affected eating and sleep...those type things. The doctor will also probably have questions of his own. But it's good to come in with notes of things to say. That way you know what you want to say, if you get nervous or panicky and forget you have your notes, and also you can ask if your friend can be with you and if its okay with the doctor your friend may have some observations, too, if you don't mind that.
I wish you all the best and hope you get some care, support, and most of all RELIEF.
*hugs*
Hang in there and remember we are here for you.