? About tracking cm and cp.

I always track my cm and cp when trying to get pregnant. This cycle around I am stumped. It's cycle day 13 for me, I've had tons of watery/ew cm my cervix is open, but it's still really firm and low. I've never had I cycle where my cervix didn't change and stay firm during O. Could this mean I didn't ovulate or do you guys think maybe I'm just looking too far into it? Is it the same for any of you girls, for your cp not to change but you still Od? help!