There are a few possibilities here, but in either case you really need to see a physician.
Flank pain, like you describe, with possible blood in urine can be suggestive of kidney stones, but it could also be caused by an infection within the kidneys as well. Although stones can sometimes just be left to "pass", sometimes more active interventions are required if the stones are too large or too numerous. An infection in the kidneys requires antibiotics. Problems with the colon, as well (like diverticulitis, appendicitis) can also sometimes cause flank pain, and these require treatment as well.
Call your physician, or get to an emergency room if that is easier. But make a call, in either case, as you need to be seen and examined.
I hope this helps. Please let me know if you have any further questions - I'm more than happy to try and help.
Take care - Dr. Fay
Edited by jcfay on September 5 2006 at 1:14 PM
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