Hello, I Suffer From An Annoying Problem And It Somewhat

Hello, I suffer from an annoying problem and it somewhat scares me ,, I am young and have pain in the nipple, and this happened because of the wrong activity towards it, after the activity it became like a burning pain and then it became red, I think it bled or put out some liquid, often it is blood, it continued It hurts me since yesterday, as it hurts just by simple contact with clothes. I put Kleenex on it since this morning (that is, twelve hours ago) in order to prevent friction with my clothes, and now I come to see how the nipple has become, in order to find a small pus-like spot attached between Kleenex and the nipple. I don't know if it was blood or something else, but removing the Kleenex from the nipple was painful, tell me what to do, I'm worried.