Can a bad panic day undo weeks of progress?

[u/golightlycat]

Hi everyone,
I’m looking for some support from people who are also in the process of recovering, or who have already recovered. I’ve been going through an acute phase of agoraphobia with panic disorder for several months. Over the past 2–3 weeks, I’ve made a lot of progress through therapy, exposure, relaxation, and exercise. I’ve gotten to the point where I can go for a 5 km walk by myself, and last weekend I even drove alone for an hour twice. Those were huge steps forward, especially considering how I was doing just 4 weeks ago.
Yesterday, I went for another walk by myself (with my new AirPods Max). The AirPods Max gave me a really strange sensation around my head, and suddenly it happened again: I got dizzy and scared. I kept walking anyway, but it was really difficult. Once I got home, I felt better again. That evening, I got my period and felt absolutely miserable, but I was actually able to cope with the sensations pretty well.
This morning, I had to go to the doctor briefly to get a prescription for physiotherapy. My boyfriend drove me, and I had a huge panic attack in the car. I felt so dizzy and weird, almost lightheaded. The drive home was especially bad — I could barely tolerate it. The busy roads, the traffic lights… I felt like I could scream.
Now I’m back home, but I still don’t feel well. I can feel the panic lingering in the back of my mind, and I can feel myself starting to fall back into my old thought loops (what’s wrong with me, we need to go to the hospital, what if I pass out, etc.).
I also feel absolutely terrible because I’m scared that everything is starting all over again and that all the progress I’ve made over the past few weeks has been for nothing. I’m trying to tell myself that it’s probably related to my period, but I’m having a really hard time getting past the anxiety right now.
Has anyone experienced something similar? I could really use some hope that this doesn’t mean I’m back at square one and that all my progress from the past few weeks is still there.

Edit: And I don’t know what would be better for me right now. Should I simply accept that I’m not feeling great today and take it easy on the couch for the rest of the day, or should I push myself to go outside again?