I'm completing day 3 post op and I just felt my PM almost in my armpit. I've been in considerable pain. Is it possible it migrated this quickly? Is it possible the EP actually placed it there? No wonder it hurts. When I move my arm it seems to push on it. I didn't notice it there before but maybe there was more swelling and I missed it. I would say it's a couple inches from the incision. I might be seeing and feeling the end where the leads come out. I saw a recent thread on PMs migrating there but they had them awhile.
I haven't lifted that arm above my shoulder, but I do move it.