What Causes Weakness, Nausea And Muscle Pain In An Elderly Heart Patient?

I have a history of prolpse micro valve Seven yrs ago I had an ablat and did not have any problems since then. I am 82 this month and wearing a heart monitor and got out of the hospital after 3 days of tests and observation. I am so weak and I shake and nauseated ( I quit vomiting) weak and generally in very poor condition. The heart doctors are supposedly monitoring my condition for three weeks. They sent in physical therapy and I just can t do it. My muscles are terribly weak myskin flakes off in large pieces I think something else is bothering my system. I have Fibromyalgia and osteo arthritis