I had my right kidney removed about 7 mos ago and though I stay hydrated and follow dr's orders, I am constantly suffering fatigue and myalgia... Why?

Not Clear. There are many reasons for persistent fatigue and myalgia after a kidney removal. There could be a medication effect, anemia (low blood count), or change in your kidney function. I would suggest seeing your doctor and reviewing your last set of blood test or obtaining new bloodwork to ensure nothing internal is occurring.