I've had a pain in my side and back that starts under the side of my ribs, and goes to my back in just about the smae place. I thought it was a muscle from sleeping wrong or something, but it hasn't gotten any better after 6 days. I don't really have any other symptoms, though. I always urinate frequently, so I can't tell if there's a difference there, and I don't have a fever that I know of, though I felt like I had a low one last night.
It is possible this could be a kidney infection?

the only way of telling really is to hand in a urine sample to doctor. ive had kidney stones (renal colic) and had the pain you have described. lasted about a fortnight. then got so bad that had to go to hospital. like you, i thought it was either muscular, or infection (which is coomon with stones) so id definately get it checked if it persists

good luck;)