Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with a doctor.
Without the ability to examine and obtain a history, I can not tell you what the exact cause of the symptoms is. However I will try to provide you with some useful information.
Numbness could be due to multiple causes. Some causes can be nutritional (such as a vitamin deficiency) or autoimmune (such as Lupus or Sjogrens) or toxins (lead) to name a few.
One major cause of whole body numbness is related to emotional/psychiatric problems related to stress. These are true medical conditions whereby instead of a patient experiencing depression or anxiety, they experience physical symptoms, and once the stress is addressed, the symptoms resolve. Fibromyalagia is another medical condition that leads to whole body pains, and is best treated with medications such as lyrica and neurontin, exercise, and physical therapy.
However, since your numbness has traveled, it could be migraines or even a seizure (but less likely). Migraines can present with many different findings. But if the numbness is constant, I would think less likely of these causes. Also, strokes in the thalamus can cause sensory changes. Thus, it would be important to evaluate this with an MRI of the brain.
You should continue working with your physician. You may benefit from an MRI of the brain if you have not had one.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.