I'm resigned now to believe that I ovulated on CD 18. I'm definitely not getting an early period, so that's good. And since the luteal phase is very likely 14 days, CD 18 fits if my cycle is 32 days like normal.
So that said, it seems that yesterday may have been an implantation dip! It was 9 DPO, and I read that implantation can happen 7-10 days after ovulation. After implantation it can take 5-6 days before the hCG levels are high enough for an HPT to pick up, so it should be on Saturday that I can get a result. Maybe. Hopefully!
Jen's Ovulation Tracker