Thank you for replying! It is good to hear from other people who really understand!
It's hard sometimes, because even people who are sympathetic and want to help just sometimes really don't understand.
It's like "I know I'm not dying. That doesn't have any bearing on the fact that I'm currently having a massive panic over feeling like I'm dying!"
It's been 15 years since that first attack, now. I still have a few every year -- and things that used to scare me a bit sometimes now break me unexpectedly. I've just learned not to be too embarrassed by it, and I've learned how to explain it to whoever happens to be with me when I melt down, and I've learned (through experience) that those feelings are just my anxiety, and not impending doom.
Most people who know me well know about my anxiety, but if you let me casually, you wouldn't know.
Except when I get sick, I function quite well these days. When I had what I still think was the coronavirus back in February, I became a wreck again, (symptoms of shortness of breath are probably the top trigger, since they'll start the anxiety, which then makes the breathing worse, which is the anxiety spiral all over again) but I recovered after two weeks, and am actually holding up well in my locked-down world.
I was probably no fun to talk to during my illness, so I owe thanks to all my friends who listened to my panicked whining for two solid weeks