Ugh - welcome to my world! I’m like this. I have been forever but it definitely gets worse as I approach menopause (maybe get your HRT tweaked?) and when I’m depressed or stressed.
Anxiety must be a horrible shock if you’ve never had it before.
Yoga and mindfulness are BAD for my neurotic brain - all that concentrating on my body makes me imagine all kinds of symptoms. I’m much better when I gave you concentrate on stuff like dance steps, sport, or something high impact and complicated. Or have upbeat music playing.
What works is - set a Worry Time (say, 4.30pm-5pm). Every time firing them say when you get a sudden fear or symptom tell yourself you’re allowed to worry about it, but only during Worry Time. That always calms me down snd by the time it gets to 4.30pm I’ve usually forgotten whatever it was. If I haven’t, then I can use that time to get a plan of action.
Don’t google symptoms. Yesterday I had endometriosis according to Google, and the day before that it was a heart attack. The day before that I had HIV. Honest.
There are lots of health anxiety forums. Interestingly, most people on there are smokers. I’m a heavy NRT user. There’s probably a connection do reducing nicotine is a great idea.
And go easy on caffeine (jitters) and booze (depletes your vitamin B and makes you more nervous/tense); take vitamins and maybe try St John’s Wort.