Apparently you don't tick the box for PEM, which is a required feature for an ME/CFS diagnosis. No one is arguing that you got a "CFS" diagnosis in the UK. Many docs there use the Oxford definition, which does not define the illness we refer to here at PR as ME or ME/CFS. Sadly, doctors rarely do enough testing to eliminate other fatiguing illnesses before they slap a CFS label on people. Have you been adequately tested for various forms of dysautonomia, for example? Your symptoms sound much more like dysautonomia than ME/CFS. Dysautonomia can result from a number of conditions, of which ME/CFS is one, but dysautonomia without other defining symptoms of ME/CFS is NOT ME/CFS. This might help: Clinical Evidence of Dysautonomia This suggests some type of exercise intolerance, which is not PEM. In many cases, exercise intolerance is treatable. If you don't want to accept long-term disability, then don't accept an ME/CFS diagnosis. I don't see why you want to hold onto a diagnosis which means long-term disability when the alternative is to seek out alternate diagnoses that are likely to be treatable. Wouldn't you rather be treated and get on with your life?