Whiteheads. Basically pimples pus-filled ones most likely the reason they are spreading is because as your wash your face the sacks pop and it spreads hnless you pick at them and leave it like that. You gotta put a anti bactetial topical on it such as benzoyl peroxide or just keep it like and dont touch it. Dont lay your face on it nothing. Dont ever let your chin touch anything. Itll natueally dry up or pop on its own hopefully in the showers and itll go away. Worst case scenario its basically a sign saying your hormones are out of balance and a outbreak migjt be eminent. Think positive.