I have heard that most gp's miss the adrenal problems despite their best effors. The tests they run are designed to sniff out adrenals problems in their final stages, same with thyroid, gluten allergies, and a host of other problems.
My suggestion to you is find a naturopath or an expert endocronologist who can run the necessary tests.
I have also been to the rheumy, neuro, pain clinic, stuffed with pills, dx'd with fibro...yadayadayada.....
I finally called my naturopath and asked her for the adrenal test. She mailed it to me and I mailed it back to the lab and within days the results were in: adrenal fatigue. Sadly, all my conventional-practice doctors are clueless....