some people had a little white bump like a pimple on the side of their breast a couple of weeks ago that was a bit tender, but now it is red and very tender. Sometimes it itches but they can't scratch it because it hurt.
the best to go about this problem
Acne can happen anywhere on your body and the breast is no exception. Just keep it clean and wash your breasts well. Since the breast is very sensitive a pimple can be very painful. You can put a bandaid over it if your bra is rubbing on it.
Sweat, dirt, and definitely deodorant can clog the pores in your skin and can cause pimples. If it comes to a head and it's painful just pop it. It might hurt but it will go away after that.