I do not have one for HS. I Have one because I have breathing problems.
You need a drs. Note and I believe you have to take it to your state representative. I wouldn't let the dermatologist dismiss you I would let her know how much pain you have; actually, she must know by now since you are in the hospital; let her know.

Do you also have a handicap parking pass? I asked my dermatologist about this and she was very dismissive. She made me feel like a fool for even asking.

Yes, I have used an electric scooter to get around. I have HS in my groin and I know how painful it is so the scooter really helped a lot.