I'm so sorry you've been going through this. Your symptoms and experience mirror mine in so many ways: pain!, tingling, fatigue, etc. I've been on a search for a diagnosis for almost 10 years.

I went to a movement disorder neurologist recently because of my restless leg, muscle spasms, and a tremor that I developed. She thought it might be Parkinson's, so she did a skin biopsy. It turned out I don't have Parkinson's, thank God, but the test results indicated small fiber neuropathy.

I'm trying to get an appointment with Johns Hopkins Small Fiber Neuropathy Center (I live in Maryland), but in the meantime I've been doing some research on SFN. I found a fantastic YouTube video of Anne Louise Oaklander of Harvard and Mass General in Boston. Her research on SFN is groundbreaking, and the video is one of the best I've found for explaining how SFN affects the body, and why the symptoms are so varied in type and location. There is a diabetes and/or glucose intolerance connection, although not everyone with SFN has diabetes/glucose intolerance.

I highly recommend the skin biopsy test. It shows the intraepidermal nerve density. Mine were low, indicating SFN. MRIs do not show SFN, which explains why my countless MRIs did not pick it up. Dr. Oaklander explains the difference between small and large fibers and why MRIs don't pick up SFN.

I don't know yet what my treatment options are, but I'm just so relieved to finally get an accurate diagnosis (I hope) of what's been going on with my poor, weary body. Wishing you the best of luck. Here are some helpful links. Let me know if you have any questions I might help with.

What Is Small Fiber Neuropathy?
https://my.clevelandclinic.org/health/diseases/17479-small-fiber-neuropathy)
Anne Louise Oaklander on SFN