You could be developing a mole. The exact thing happened to me on the side on my breast about where my bra hits. It felt more skin related than a lump in my breast (I would have flipped), but it has slowly become more brown and appears to be just a small mole (I hear they can crop up too). Maybe it never fully developed when you were pg the first time and now it has been revitalized.
And yes, I also have a few skin tags under my arms and near my breasts ( i guess if fabric rubs too much it can exacerbate the problem). They are kind of gross but usually only noticable to me.
And yes, I also have a few skin tags under my arms and near my breasts ( i guess if fabric rubs too much it can exacerbate the problem). They are kind of gross but usually only noticable to me.