I was taught some techniques by a counsellor that help me with overwhelming anxiety. They're all about calming down the nervous system rather than trying to engage with your thoughts. Apologies if you already know them. They sound a bit out-there but I've found them all useful at different times.
4-6-8 breathing: breathe in for 4, hold for 6, breathe out for 8. Repeat as many times as you can.
Low humming, or making the deepest "vuuuuu" sound you can. Breathe in and repeat.
Slowly breathing in as if through a straw.
Making a v with index and middle finger and then slowly rubbing one finger in front and one just behind your ear, up and down.
Frozen veg packets on your cheekbones.
Doing great big giant steps and front crawl motions with your arms.
Standing on one leg with your eyes closed until you start to wobble. Then on the other.
One hand flat on forehead, the other flat on the back of your head just above the nape of the neck. Hold this position and breathe in and out a few times.
Prune Harris's videos eg the daily energy routine - really good for shifting the horrible uneasy feeling of difficult emotions out of the body.
Hope you can find something that works for you.