Im not really sure on mine....I had laproscopic surgery and a D&C and hysteroscopy done in the very beginning of January. I bled for almost a week after...but did find out I was ovulating durring surgery. (GOOD NEWS!) BUT....I didnt have an actual period until beginning of this cycle so....cut to the end of the story...I had bought the OPK to use once my period came...and started having wierd ovulation symptoms and checked and got a pos OPK in the first few days, and then a neg the next day. So we BD for 3 days and on the third I had what im guessing was Breakthru bleeding for 4 days then had the same symptoms again and used another OPK and got a Pos for 3 days. So im guessing that the second was the O time...but then 13 days later I got AF full blown (much less painfull from the surgery...thank goodness, I used to be useless for 3 or 4 days durring AF pain was that bad I was on narcotic pain meds for them) So this is the first month I hav actually tracked every day...before surgery I was on BC for 4 months had horrible cycyles that were giving me periods every 2 weeks or so...but before that I had long cycles of anywhere from 30-40 days. WHEW that was alot to write....hope I didnt confuse y'all!