Have any of your doctors mentioned Benign Fasciculation Syndrome? It wouldn't explain all of your symptoms, but would explain the twitching, burning, tingling sensations as well as cramping. I've had it for the last 9 months, following a bad viral illness. It is all different places in my body, and moves around. Sometimes it follows times of stress as well. Mayo has a benign fasciculation forum on here as well. It might be worth looking into.