Ttc. Spotting.

Cheyenne

Ttc. Ovulation on October 4th. Sex all days of fertile window with male ejaculation. Started spotting 6 days before period. (that's never happened before) still lightly spotting 3 days into my supposed period (total of 9 days spotting very lightly) but I usually have a very heavy flow and insane cramps, I'm having neither. Took 6 pregnancy tests, all negative. Sooooo confused......any ideas?