Does this mean I ovulated the 13th ? I had sex on the 12th but didn't know I was ovulating the 13th because glow apparently changed my fertile window (before it was in the beginning of the month) when I started tracking my temps everyday. I randomly just had sex with my boyfriend the 12th then a couple days later that's when my fertile window changed and I found out I ovulated the 13th according to glow and the 12th was the highest percentage. So what I want to know if this is accurate did I really ovulate the 13th?