Found new lump in dissected armpit this morning.

My self discovered lump in the other armpit (hadn't even finished chemo!) turned out to be a schwannoma - had to look it up but critical information was that it had probably been there for ages and was totally benign. We all fear the worst. You do have to get it checked, by whoever seems appropriate, but take heart, it may just be one of the weird but harmless things our bodies have that we don't know about! Best wishes.