I don't know if this'll help or not, but when I was first bf'ing my ds, I developed a row of small, white, almost-blister-looking bumps. My lc said it was a positioning issue. I fixed the position & they went away. It happened again a couple of months later when I got a little lazy. I corrected again & they went away again.
Since yours is a single spot, this may not have anything to do with what you have, but I wanted to throw it out there.
Hope it heals soon, whatever it is.