@TheVorticon I know how you feel and understand the anxiety it causes. Having recently had issues with my mental health which resulted in a lot of distorted and unhealthy thoughts I can honestly say it isn't fun at all.
One of my friends suggested listening to music that is peaceful and has no lyrics, because sometimes the songs with words can in fact add to the stress we are dealing with. Another friend suggested doing puzzles like sudoku or word finders. They challenge the mind and keep it busy so that you are no longer thinking about what is causing your anxiety.
Hopefully they can be of assistance to you!