Tmi overshare question--I've never been one to experience soreness in my breast during period or…

Tmi overshare question--I've never been one to experience soreness in my breast during period or Ovulation. My period has come at the end of the last two months so despite the fact that I have an irregular cycle It could be coming. All of a sudden the last two days I've been having pain in my armpits down into my breasts. It aches and I even had to take Tylenol for it. Is this the type of "tenderness" people talk about? I have a high pain tolerance and I find it very uncomfortable so I'm kind of concerned.