Super sore nipples..?

This is a tad embarrassing, but my nipples have been extremely sensitive and sore lately. Like I can barely brush my hand or arm or whatever past them and if it touches them it hurts sooo bad! Has anyone else had this issue before? Was it just pms or was there more to it? I just want to know why they hurt so bad..it's been this way for nearly a week! It's really weird..