What Causes A Sensation Of Weakness In Thighs And Shoulders While Walking?

I am 64 years old. I developed a weak feeling in the tops of my thighs a couple weeks ago and thought it was from increased exercise. Then I experienced the same thigh symptoms with the same sensation across my shoulders down to my elbows when I was walking. After sitting it went away fairly quickly. I then had a few days of cold and fever and slept a lot and since then (3 days) whenever I stand and walk the weird feelings start in the thighs and progress quickly to the arms, I start to feel faint and when I sit down they go away in the reverse order, but while sitting and waiting for it to leave I can feel my heart pounding. My medical history is depression an gastric bypass 10 years ago. Meds are sertraline 200 mg daily and gabapentin 200 mg daily. My question is could this just be something viral or should I see someone? Thank you.