I am having pain on my left rear above my buttocks. I also have pain when walking where I get so winded that I need to sit and catch my breath. I originally thought the pain was a muscle but now am connecting the pain with my weakness and shortness of breath. My dr. Sent me for a stress test about a year ago and a recent pulmonary function test but both were normal. I am taking thyroid, blood pressure , and metforman and cholesterol. I don t know where to go, should I see an endocrinologist, could this be a kidney problem. I really need help but I didn t think this was something to go to the emergency room for, as if I just sit, I am not in so much pain and I am not winded or feel faint.