Full body muscle twitches, internal tremors at night when fallng asleep, random numbness tingling. anxiety!? other ideas? clean mri, emg, echo, blood.

Magnesium: Ask your doc to measure your electrolytes. A low magnesium level, for example, can produces muscle twitches, headaches, etc. It's easy to raise that level w/supplements. If it's a different mineral your blood work will tell you. They all need to be in balance.

Probably anxiety: See a psychiatrist. Medications and psychotherapy would help. Seems like physical exam and tests are normal.

Anxiety: Yes this could be symptoms of anxiety or other disorder. Be sure you are living a healthy lifestyle without alcohol, drugs, or smoking, and eating a healthy diet. Are you having high stress symptoms? Normal periods and normal weight? If anxiety is the problem then you need help with this. Use meditation to relax, exercise more do not use stimulants.