My husband has it. His problem is being among people: he would have been OK with the doors open, as this would have made it easier for him to get outside and away from the people.
He used to be able to go to a function like the kids' school concerts, as long as he could sit near the outside door, and go out when he needed to, but these days he would not be able to consider going at all.
I don't drive any more, so he has to take me food shopping, but we do it quickly and often have to go home before we've finished. He curses and whinges the whole time we are out. But it is just as well i don't drive, or he would get worse, I'm sure, and never go out. I do other shopping by public transport.
He won't go into the back garden either.
If you go to the Doc, be careful what they prescribe - my husband is coming off anti-depressants as the side effects were too bad. I think counselling would be better. My husband won't do it though. Talking to a stranger is more than he can bear.
He thinks he got a delayed form of PTSD, as he got worse and worse the more he remembered his early days in Special Boats (a branch of the RN submarine service where they do special ops). When you get older you tend to remember the old days more and more, and he'd rather not.
Yes - I would recommend counselling by a good psychologist.