How Can Aches In The Arms, Legs, Hip, Back And Ankles Be Treated While On Letrozole?

lumpectomy with radiation 2014. taking letrozol and valsartin. since May 2018 I have been exhausted, with it getting worse, Since Sept 1 2018, had chest cold, sneezing, eye cold, and great debilitating exhaustion.Aches in knees were common to letrozole, since Sept. aches in arms, legs, hips. back ankles. my energetic life style has been reduced to constantly falling asleep, napping, and debilitating exhaustion. New internist suggest PMR? i don t thing so. thoughts??