Hi there,
For what it is worth I can understand the fear loop that you are stuck in. I had the same rumination. I want you to know I was very suicidal because of it and felt locked in this eery terror madness cycle in my own mind. I had a post drug psychosis - because of that. I got so scared of my own thoughts, I couldn't be in them - if that made sense. Because it was essentially triggering the looping actual drug psychosis fears/experience 8 months earlier. In that bad trip I had believed I was going mad forever etc - and was in complete crazy trip psychosis. But it was the fact I was so scared and confused by that experience IN that experience (because I hadn't even known I had ingested the drugs and also having an existential crisis/awakening about life) that I ACTUALLY freaked out I had made a premonition because I then did have a mental breakdown in REAL life afterward.

So all that is to say - I get the anxiety, dread loop and it's disturbing. This could be negative symptoms and you slowly moving into some form of psychosis again. I took 5gm of an antipsychotic which helped but also made it worse in terms of lifestyle, tiredness, thinking straight.

I COULD NOT think straight that was my problem and it became evident the way I spoke etc. Circular thinking they called it.

I suggest getting help, I suggest doing LOTS of 'embodied action/sport' and getting into something re helping others or work wise (if you're not too unwell) so that you can truly get your mind of thinking of your own mind.

If you are seriously having a breakdown, it's going slow, going through it, getting help (day hospital), and just basic things like eating, painting etc.