Trace amount of blood in urine and pain in abdomen

Patient: Hello. I have been experiencing a slight pain sensation in my right abdomen near where the appendix is located as well as in the lower back and immediately I was concerned it could be appendicitis. I went to my university health center yesterday to get some tests done and my WBC count came back normal. However, in my urine there was a very trace amount of blood. I am aware there can be many reasons for a little bit of blood to be in my urine, but in combination with the slight pain and also an increase in frequency of night time urination has me a little concerned. A friend of mine suspects a UTI, but the WBC counts seem to indicate otherwise. Is a UTI still a possibility, or is it more likely something else, like small kidney stones. Thanks!