Nipples in serious pain

Okay. According to glow my fertile week starts Tuesday. I haven't been tracking anything because I had a miscarriage last month and don't wanna be disappointed when I don't get pregnant again. Well my nipples hurt soo bad ! And the sides of my breasts hurt. Just wondering what could possibly be the cause of this ? Could it be because I'm ovulating or will be soon ? Would just like some input. Thanks in advance ladies .