Sore nipples!? Kind of rambling.

Okay, so I'm either 5dpo or 7dpo... Or I could be completely wrong. I didn't use opk this month, I'm going based off the O window between this app & ovia, and how my cm was. Anyway, my boobs usually get pretty sore a couple days, maybe a week before AF. I got my hopes up last month was suuuure I was pregnant. Uhhh no, all in my head. So yesterday I noticed my nipples were kinda sore, which seemed weird.. But today... Omg. I feels like I stick them in. Vacuum hose for hours. I just got off BC in feb. So I've kinda written off a lot of things to be my body still freaking out from that change. I've been pregnant three times, but with my first two I was really young and didn't even know until I was 2-3 months along (irregular AF, never paid much attention) and the third resulted in a miscarriage at about 8-9 weeks. I found out about that one early, but never had any symptoms except late AF and bloating. Could I be over thinking this? Could it still be from getting off BCP? I've never noticed them hurting before!