What Does Bleeding Between Periods With UTI Symptoms Suggest?

Hi, I went to the doctor last week because of a possible UTI where I discover that I actually had one after the doctors ran the test, they told me to go home, and drink cranberry juice and water, I am bleeding between my periods very light blood,bus this normal? I only drink cranberry juice every once in a while like one every 4-5 days should I be drinking more? What can I do to stop the bleeding?? Doctors ran test and everything came back normal.