I have Fibro and ME, there's no blood test for either. I'm afraid they are usually diagnosed on the basis of a lack of diagonsable condition ie they can't find any other explanation for the symptoms.
My symptoms are similar to yours, exhaustion, pain, restless legs etc. There are drugs available to help elevate but not cure I'm afraid.
I was diagnosed with ME in my 20's after a bout of pneumonia and pleurisy. I never recovered. I was diagnosed with Fibromyalgia in my early 30's.
It's a life altering life limiting condition that affects different people differently, and is changeable hour to hour. One minute I'm having an OK day the next I'm slurring my words and can't keep my eves open. Don't get me started on the pain! It never goes away.
Feel free to pm me anytime. There are a few support groups and therapies and I've found a few things that help.
Good luck and rest rest rest. Xx
Tommy Robinson arrested. Police using their existing powers