I know we've had this question before, but I'd love to hear your opinions again!

Ovia and FF are giving me totally different "fertile window" dates, and I don't know which to believe! I actually only track my period and sex--no temps, cm, opks, etc--because I'm totally type-A and I'm afraid I'd just go nuts with it, but the differences are making my head spin...!

Adding screenshots since they're so different!