Always late for the party these days, and I'm not even attempting to make an entrance!
So sorry you've been struggling with this, and at such an important, stressful time for you
I do the heartbeat focus exercise as mentioned earlier, coupled with a visualization exercise.
I look at my thoughts on display centre stage. One by one I sweep them away into the wings with a giant witch's broom. Everytime they pop back onto the stage I sweep them away again, the aim is to get the stage as empty, dark and peaceful as when the theatre is closed.
Takes a while with racing / intrusive thoughts, but I get it right eventually. And then, because looking at a pitch black stage can only do so much.........
I picture a calm soothing setting. Usually me (with boobs

) on the edge of a cliff watching the waves....
Because we all know how calming a pair of nice breasts are Right?

lol
I hyperfocus on this thought, the sights the smells, the feelings it evokes, and then I usually pass out unknowingly and wake up refreshed
Sounds like a long dreary process, and can be initially, but with practice each step becomes more familiar and easier to accomplish.
My broom used to work overtime when I just started you should see this baby go now!
Disclaimer: I made all this up one night a few years ago when my thoughts were racing and looping like crazy and I had no dx to soothe my scared frazzled mind. So I have no idea if it will work for others.
Hope you're doing better now C