Feel like it’s impossible to be in my own head?

It definitely sounds like depersonalization which is super common with anxiety. Since depersonalization leaves you feeling outside of yourself, why not try grounding, which would be the opposite? Like, take a few deep belly breaths and as you do it, notice in detail all of the sounds you hear around you. Really focus on it. What are all of the sounds that you hear? Then do the same for smell. What smells can you smell? And you do this through all 5 of your senses while continuing to deeply breath. And see if that helps bring you back to yourself and the present moment. And keep in mind that what you are experiencing is so so common.

Hope this helps

I totally got that, several times. It could be terrifying until I found out what was going on. Beautiful is right, grounding is one of the best counters to this symptom. My method is to see 5 things, hear 4 things, touch 3 things, smell 2 things, and taste 1. Learning how to cope with it is a deeply personal challenge, and while I'm sure you'd rather decline the opportunity, it is a battle worth fighting and reclaiming your faith in yourself. That was what I found most upsetting; that I was so frightened by my own mind. When you're not experiencing an attack, it is worth your time to learn meditation, because that discipline eventually helps you direct your focus outward which keeps the spiralling from continuing. There are definitely things you can to to help yourself, and to reach out and find help from others.

Untreated anxiety, sure. Are you seeing a doctor?

I'm not familiar with those (except I heard that violinists use them to settle hand tremors to play better). If they ease the shakes but don't help with the anxiety circuits in your brain it might be a case of treating the symptoms and not the cause.