Hi, I've read your thread and am so pleased that you have a GP appointment.
I had bad anxiety, with the same kind of intrusive thoughts. They were awful and paralysing, and the panic was horrendous. The thoughts went round and round in my head, and when I thought I had rationalised them, they kept going. It was an awful time of feeling very alone.
What helped initially was Sertraline. It quelled the anxiety enough that I was able to engage in CBT, which was brilliant.
I don't know if it helps, but I was taught that we all have different random thoughts in a day, floating through our brains, and the fact that we were noticing the worrying thoughts, didn't mean they were true. Kind of thoughts are not facts (obvious to you I bet, but I needed help to really get that). And if we try and stop the thoughts, they come back more. CBT taught me to look at the thought, think "meh, there's that thought again", and watch it drift away. Over time, they stopped.
I don't mean this as a me-rail. I just wanted to share because it can be so lonely having anxiety, and I don't want you to feel that.
Holding your hand with this OP 