positive ovulation tests

Hey everyone, I am in my first month of trying to conceive. I have been testing for ovulation everyday since the end of my period. I received all negatives until nov 3rd I had one that was basically just as dark  as the control line but I was still unsure if it was positive. On cycle day 20 I received a blatantly positive ovulation test and I have continued to have positive ovulation tests since (5 days in a row). Has this happened to anyone? If so what was the reasoning?