Just about a week ago I got over a full week anda half of derealization and questioning my reality(ie. Why am I me? People see things in first person like I to and have their own thoughts) it was really scary and honestly I felt like it was never going to go away
But it was caused by upping my medication and my brain getting used to it. So that could be your issue as well. Because before I upped my medicine I had a full week of constant anxiety. And not just low simmering anxiety, I mean I was shaking, emotional, unable to eat or do activities. I was bad.
So just know you aren't alone in derealization and it does infact go away. You just have to try and tell yourself it's just anxiety and that it can't hurt you or make you go crazy. It's just your mind playing tricks on you due to chemical unbalances in your brain.
It'll all get settled. You just have to believe it will. Google "dealing with derealization" or anything else along those lines. That's what I did and it helped.
It takes time but it's something you can kick to the curb.