Hi,
Welcome to HCM.
If you are spotting (through the vagina) after a heavy bleeding, then
pregnancy should be suspected. so I will advise you to check urine pregnancy test again for confirmation.
It can because of flu but should ruled out by clinical history and examination with some blood works.
Urine test should also be done to actually check the UTI (which might be the cause of the spontaneous
miscarriage).
If there is no pregnancy, then you need to see a gynecologist to determine the cause of your
abnormal vaginal bleeding.
There are a wide range of causes that will need to be excluded one after another.
If
urinary tract then a course of antibiotics should have been started.
Your bleeding is not a UTI but if pregnant then could be the course of your bleeding as a pregnancy complication.
First step is to do a pregnancy test. Next step is see a gynecologist urgently irrespective of pregnancy test results.
Continuous bleeding can lead to blood shortage/
anemia which can seriously complicate your health.
Hope this helps.
Regards,