So before I got a positive opk glow said I was supposed to ovulate on the 29th just like my petal app said. So I got a STRONG positive opk on the 26th and glow switched things around and put my ovulation day is now the 26th. I also got a STRONG positive on the 27th. But on my other app it didn't change still says the 29th. I'm just confused on did I ovulate on the 27th or on 29th? I did keep taking opks and after the 27th they went negative.