Anyone period start on the 13th?? I wanna see my cycle buddies.

I got my period at 12Midnight the 12th into the 13th.... so like super confusing but I should tech use the 13th as my first day correct ? That’s what I did but I feel like this calendar is always wrong on predictions.

Any tips on how to check cervial mucous? I try but it comes out clear and not a lot and stretches very tiny bit. I think I’m doing it wrong.

& best way to predict ovulation in your guys experience- anyone’s experience not just anyone who’s on my exact cycle if anyone ... 💕