I Was Told Two Yrs Ago That I Have Polymyalgia.

I was told two yrs ago that I have Polymyalgia. I've been taking a steroid and it has relieved the pain. Now I have developed pain in my back and pain and burning in my legs. It's worse when I get up in the morning and get some better as I go through the day. My Dr. doesn't think it is caused from the Polymyalgia. It t's a burning aching feeling in my lower back and lower legs. Any suggestions? I'm 81 yrs old