What Causes Yellowish Stool With Back Pain?

A couple of weekends ago I had to urinate too frequently and quite had quite frequent bowl movements (but not diarrhea.).A week later -- yellowish Brown, to more yellow stool, and some lower back pain as well. My stomach "gurgles", feels generally sour or acidic. Also, at the same time a dark puffiness has developed under my eyes. Which gets worse whenever my stomach "churns" up and feels acidic...