What Causes Right Flank Pain While Suffering From Fibromyalgia?

hello, I am a 44 year old male, with fibromyalgia and chronic pain most of my life, since easter I have had pain like a dull ache in my right flank area of my lower right back, hurts to stand straight and walking makes it worse, been to family doc she did a urine test no infection present but moderate blood, I have have microscopic blood for years unknown cause, recently was on predisone for about a week with no significant improvement or relief, overall sick feeling and total lack of energy for last 30 days, now pian is getting worse and seems to be moving to the left side