What Is The Vibrating Feeling In My Feet Radiating Upwards?

I have experienced a "buzzing" , vibration like sensation beginning in my feet and moving upward. I feel it in my upper body as well. It has progressed over time. It is NOT painful, but it IS annoying. It seems worse in the morning and I feel it most while lying down. I am 61, female, in generally good healtth, but w/ medically managed hypo thyroid and fibromayalgia issues of long duration.