It did all catch up with me at once. Looking back on it now I can see that I had been getting worse for a long time and then I got sick and hit my absolute bottom. I spent a few weeks feeling like I was not in my body and that I couldn't turn back into being myself. It was SO odd.
I can't diagnose you, but I'll tell you most of what you type sounds very familiar to me and I have anxiety issues - panic disorder and OCD. I worry that I'm going crazy, but it's all worry and anxiety and nothing else.

You are not alone.
I'm too scared to even try my Ativan, so I'm probably not a good one to talk about meds. I am sure they help though. Sometimes I wonder how I'd be doing if I allowed myself to seek that type of help.
I hope you have a good session with your T tomorrow. Talking about it will help. Therapy has helped me a TON. Tell your T everything that you've been posting here. It's amazing how much just being HEARD helps.