I made a little diagram for all of you to see
1.-Is a recent lump that had grown on her back, the vet says the consistency pretty much suggests it's just a skin cyst
2.-Is the one I was worried about, it's about the size of a nailhead and the skin is discoloured. She says this is probably a mammory tumour and will have to be removed along with the nipple, but i's very small and can be done with a local anesthetic.
3.-Is more worrisome, it's a larger, peasized lump that is attached to underlying tissue. She says this is quite deep and Rista would probably have to put under to have it removed.
For those asking about lumps and were worried, the thing to remember is 1.)Is the lump attached the skin and can be easily moved around? Or 2.)Is the mass attached to tissue underneath and seems more fixed in place and the skin moves over it. If the lump is a 2, you should have it checked.