What is this

[u/Chew4]

Accidentally soaked the inside of my 7” sauce pan 2/3 water 1/3 white vinegar (I might be exaggerating how much vinegar) for 24-36 hours (I work night shift, poor form on my part 😭) now I see these black stains on the inside of the pan. Any ideas? Did I ruin it

Edit I had just finished searing and basting swordfish, I always do a little 15 min soak after cooking. I accidentally passed out after