Why are my boobs so sore

For about four or five days I've been having super sore nipples. Lightly brushing them is bothersome. I had mirena taken out over two months ago. Had my first full blown period august 5th of five days. I haven't had a period again but I started birth control pills Sunday after taking five pregnancy tests to make sure I wasn't pregnant and starting birth control(all separate days). My boobs are never like this. The last time they were remotely this sore would be when I was breastfeeding, which was seven years ago. I am sexually active and before starting the birth control pill Sunday we only used the pull out method. I wouldn't say I'm pregnant because all the test were completely negative. Any advice why they could be sore? Glow is saying my ovulation day would be the 23rd since I haven't started yet. 🙏😫