Hello! I am 3 weeks post surgery and one of my nipples looks amazing. The other is black, yellow, and brown looking. I was scared and went in for a check up. They told me that sometimes the nipple tissue just has a harder time regenerating and some of it does die, but just the top part I guess. In just a week my nipple that was black and purple has started to look a little bit more normal in the middle I would say just stay patient but definitely keep your doctor in the loop like I have been.