1 month PO breast reduction. Redness and itchy around one nipple area, what is this?

I had a BR done last month, the left breast was larger, more was taken out but the nipple opened a few times and had to be sewn back. I do not have a nipple there, just an indent and still once in a while a few blood drops come out, but most concerning is the circle around the nipple is red and itches a lot, what is this? It feels differently, just rough feeling.