Talk to Gynecologist on Iam 15 Yrs Old

am 15 years old. A few months ago, I started experiencing breast pain a few days before my period, but only when I touched my breasts. The pain would go away after my period ended. However, since this month, I have occasionally felt a mild, sudden shooting pain in one of my underarms. It lasts for a moment and then goes away. My periods usually come toward the end of the month, so they are not due yet. I am feeling worried because I don't have any lumps, but I am experiencing sudden underarm pain. What could be causing th