If you can afford it then get health insurance so that you can nip worries in the bud. If not, just go to your GP if you have a weird symptom and get your worry ruled out.
You can get a huge amount of symptoms with health anxiety - quite severe ones actually - that army real.
No more panic.com is a fab forum to chat and learn about dealing with health anxiety.
For sleeping try you-tune “meditation sleep talk down” and listen to a meditation, listen to every word and it will block out negative thoughts and send you to sleep - some are too short - I like the 30-40 minute ones. Not all of the voices will appeal to you but once you’ve found one you like, they are great.
If you have a worry - deal with it head on.
I totally ruined my holiday last year obsessing in case I had bladder cancer because the go found a microscopic bit blood in my urine. I developed other symptoms after I’d googled them and ruined the holiday for everyone. I had a cystectomy when I got back - I was clear, and surprise surprise the symptoms went. I have loads of stories like that but now that I deal with it immediately and get checked, I am much better.
Tell your GP how you feel.
Good luck.