Tracking ovulation without OPKs

I've been trying to do this, with the assumption that I was really in tune with My body and that I could feel ovulation, WRONG! I had a routine transvaginal scan and I asked if I ovulated. Cd 18 and my dominant follicle was only at 17 and no ovulation yet. I would probably have stopped BD'ing by now! OPKs were ordered the same night. 🤦🏽‍♀️