21 days late

Hey y’all.

I’m 21 days late today and I’ve had negative pregnancy tests (other than an indent test last week which got my hopes up lol).

I ovulated last month, confirmed with BBT and OPKs and also my resting heart rate on my fitbit.

I’ve not been stressed and made no lifestyle changes. So what could be causing the late period? I’m just wiling for it to come so we can keep trying.