Snufkin, sorry you struggled a bit there.
I have to say out loud sometimes, "Stop!" when negative thoughts get started. Really I can ill-afford to spend a lot of time in the past. Lot of stuff I could beat myself up about. I choose not to, though.
This dies down with some continuous sober time. Give it months, not weeks. In the meantime, I always played instrumental classical music - no thought triggers, and it's calming. We have streaming radio here where I can choose the genre of music. I don't know if you have Pandora, but that's what I use.
Change your thoughts. Look at pictures of birds or flowers on the internet! Also, fifty jumping jacks will settle the nerves. I did that a lot in early days. Still do some mornings if I wake up anxious.