Ovulatio, Spotting.....Maybe?

Brittany • Chloe Elizabeth 7-30-13. Sophia Grace 10-15-15. Baby #3 09-20-16
Ugh I've been spotting on and off since about Friday. I took an OPK test last Wednesday, it came back positive. Friday I go to the bathroom mid afternoon at work and notice only a drop of very pale pink blood, almost unnoticeable when I wiped and that was it for that day. Same thing on Friday through Sunday, only noticeable one time when I wiped. Then it stopped. Now it happened again today. Only noticeable once when I wipe, nothing more. I assumed it was ovulation spotting, but it shouldn't last this long, as my last fertile day according to Glow was Saturday. My cervix has been very high, almost hard to reach, very tightly closed, and very soft this entire time, including when I was supposedly 'ovulating' can someone shed some light as to what could be going on, please?