Hi, I Am On The Coil And Have Had Stage

Hi, I am on the coil and have had stage 1a1 cervical cancer and subsequent clear smears since. I have never got to the bottom of why I bleed between periods, this started in 2008 or earlier and has continued since the birth of my child in 2013 (prior to cervical scare). Because it scared me, I am constantly worried about it returning. I recently had a water infection 5 weeks ago and had antibiotics but the symptoms of a frequent urge to urinate and a pressure in the very bottom part of my vagina has caused me to go to the doctor worried that I may have blood in my urine. He said I did have blood when he did a dip test but that's because I was bleeding. He gave me norethisterone for 10 days because he said he wanted a urine sample when I wasn't bleeding (which I always am having had the coil fitted back in November 2015). The doctor said take norethisterone for 7 days and then bring back another sample. Having taken it since Tuesday (this is now Saturday morning), I am still bleeding (although less). Does this mean it could not be down to hormones but something more sinister?