I have a very rambunctious 9-month-old puppy, who recently jumped up to greet me, and her nails were so sharp, she REALLY hurt me above
my left breast, almost to the shoulder
. (We have since gotten her nails trimmed!) She left a bruise, and one night, I touched the bruise and, to my surprise, found that underneath that bruise was a pea-sized lump. It is in a place that one would not notice when doing the regular breast exam, because it disappears when you raise your arm to do the exam.