I have very similar symptoms. I was diagnosed with Benign Cramp-Fasciculation Syndrome (CFS) almost a year ago.
I have fasciculations (like when your eyelid twitches, but all over the body) and cramps (like charlie horse cramps, but again all over the body).
It was very frustrating to diagnose as all of my tests: MRI's, 78 vials of blood (and counting), nerve conduction tests, electromyograms (EMG) have all been negative.
I've been seen by so many "-ologists" that I've lost count.
The Neurologists says that says that CFS is just a "junk term" for people who have the similar symptoms. Some may have abnormal blood tests, MRI's, EMG's or nerve conduction tests, and some don't. Many of us have different things that set us off.
My best suggestion is for you to visit: https://www.************/groups/ISAACS.PNH . This group has been essential for me to help me keep me from losing my mind. Everyone there is very knowledgeable!