Is it cancer or hormonal changes?? help?

im 15 year old and a few months ago my rght started to hurt for a while nd the left one hurt only a little then my period came themy pain subsided but it still hurt a little and the nipple became all swollen te tht stoppd but now i feel the bottom of my has a somethin har but it hurts wen i touch it nd the other also hasthe hard thing but not as much as the other one can sumone help can ths be hormonal or cancer pls hlp me im scared