Help!

Ok, so this is weird, but I don't have any clue what is going on! My breasts have been pretty tender lately, fixing to ovulate. However, tonight I was changing my clothes and noticed this yellow crusty looking stuff on my right nipple. Maybe too much info, idk. But has anyone else had this?? The only time I ever had any discharge from my breasts was when I was breastfeeding. We're TTC #3, but I've never experienced this. I wiped it off and it became super sore so I put coconut oil on it. Just curious if anyone else has experienced this?