Sore Nipples!

So I'm on CD 27, 6-7 DPO?

I ovulated around CD 20-22?. I just got off the pill so I don't know when I'm going to get AF, irregular before and irregular again, I think.

Anyway. My nipples have been so sore since CD 22 and this has never been a normal symptom for me.

Is it pms? Could it be pregnancy related? How soon in your pregnancy did your nipples start hurting?