I have only been checking my CP for this cycle and I thought that after ov your cervix becomes low, firm and closed. I am 4dpo and have just checked my CP and it is low but soft and slightly open.
Your CP moves down after Ov, even if your PG. (It would then rise again, but it varies greatly from woman to woman. Most thoughts are that it's not a huge indicator of anything so isn't a wholly reliable sign