This app confuses me

Allie • 22 , TTC Baby #1

For the past week my calendar in this app has said I was expected to be at my peak for ovulation today (bodily symptoms also lined up to that so I assumed it was correct) my bf and I BD late last night/super early this morning, and I took another opk around 3:30 this afternoon (I know it’s not necessary but I was double checking everything). The opk was negative with a very faint line but slightly darker than they have been. After I logged the opk and everything all of the sudden my calendar changed my expected ovulation date? Could this have been because I logged a negative opk? I’m confused now as to what to believe and when we should really be BD....