I would advice you to get tested for food allergies too - very important to eliminate those foods from your diet. This can be done at US BioTek. I'm in no way affiliated with this company, I'm Belgian and this was the lab that my dr uses for his patients.
My dr (an ME/CFS specialist) sees CFS and even ME merely as a symptom of a disease. That disease would be, for most of his patients, a TBD. If you can't find a dr in the UK, you could always cross the water and come to Belgium - lol.
When I was finally diagnosed with Bart & Lyme I was so relieved I could officially get rid of that CFS brand, cause 'conventional' treatment for that just sucks... I never even tried it. I would never say to a dr that I have CFS, cause that would mean that they would immediatly classify me as a nutcase.
I was so relieved with that diagnosis, and then I got soooooo angry for months and months - lol.