Yeah, Username, breastmilk is supposed to be good for healing, as it's got immune cells in, as well as antibodies, & goodness knows what other magic. So if you do get sore/cracked nipples, dabbing a drop or 2 of breastmilk on them, then letting that air dry, then maybe putting some lansinoh/equivalent on the dried nipples to moisturise, I found to be really helpful.
I had exactly the same experience, Coco. An "easy" time as my DS mostly seemed to know what he was doing (a tough time in other ways as he was/is a hungry fellow, & is still boob obsessed even though we weaned fully a few months ago, but that's a separate thing), but I still ended up with really cracked nipples one day very early on. It was actually the day all the visitors descended, & I foolishly tried to be sociable & breastfeed discreetly in front of them, even though the bub & I hadn't gotten the full hang of the latch yet. So I tolerated a few bad latches for the sake of discretion & not waving my nipples around in front my FIL, instead of doing what I was usually doing & repeatedly unlatching/relatching him till it was most comfortable. My nipples were a bit wrecked by that evening & I had to really tend to them for a day or two. But they healed up quickly again, & toughened up so to speak within about a week, I think.
I needed to express (either by hand, or with my pump) a fair bit in the first few weeks, as there was one bit of my boobs that was prone to getting lumpy & a bit sore. It settled down as my son grew & got more efficient at draining all of my breast during a feed, but I think it was a life-saver for me. I was lucky & avoided issues with blocked ducts or mastitis.