My tests are largely normal too - but I am sicker than a dog - I am having swallowing issues, weakness, etc. and I had the MG diagnosis and now they say I am not (so I lurk here...).
My biopsy came back with all sorts of stuff on it - rare atrophic cells, cox mitochondiral cells etc - and they tell me it is NORMAL!
I fail (or rather, am normal) for EMGs, but have an abnormal SFEMG. But I am twitching (I have a muscle under my eye that has been going for 3 days and sometimes my hand and other things go) and I have no power, no stamina - but the docs just look at the EMG and pronounce me a-ok.
I also have had a bunch of endocrine issues - Cushing's was my biggies so they keep saying steroid myopthy is my issue but now for 3 years my steroids are at normal levels. Besides, how can they say steroids causes my weakness and pain and OH YEAH, you want to treat me with more steroids??? The ones the beat me up I produced myself, so no way I want to take more.
Hang in there.