my right under arm has a rash which itches and looks like eczema. ive never had a history of eczema or any food allergies. it has been about a month and not gone away even if i stopped scratching for a couple weeks and stopped using my regular deodorant. about a week ago, a lump about the size of a grape formed. i stopped breast feeding about 2 months ago. so at that time i was used to sore lumps but since ive been dry for these two months and the lump is more painful when touched.