lactating...I think

Camille • We were TTC after recommendations from my OB/GYN because he discovered I haven`t had a period since February 2016. I had a son August of 2017! And now I’m waiting to try again until my son is 2!
So I've noticed that my nipples have a yellow/nipple color crust on the tips. I try to wipe it off but it doesn't come off. After further annoyance I am able to pick it out and it's like ball shaped. Anyone know what this is or what I can do about it? Picking it out doesn't see good because then my nipples are soooo red.