What Do Pink Pimples Appearing Over The Breasts Indicate?

Hi, I've been noticing pink pimples appearing over my breasts (particularly the left one) and ive never gotten these before. Also, my left breast also seems very bumpy on the bottom. I think the bumpiness is due to my hormone levels changing b/c of pcos. My left breast randomly experiences severe pains aswell.I'm 17 and im scared if its something much more serious than i think it is. Please tell me why I'm getting pimples on my breasts. I'm 5'3 and weight 140 pounds