Sore breasts since the end of my period

So normally I have sore breasts 2-3 days before and during my period, and then the pain goes away once it's over. However my breasts have been super sore since my last period, which was about two and a half weeks ago. I'm not pregnant, but it's really bothering me as to why they're still so sore. My diet hasn't really changed between last month and this month, and I always wear a strong and supportive sports bra when working out. I just wanted to know if anyone else has experienced this. If so, did you do anything about it?