I had one, too! Stranger still, it was in my armpit, which apparently contains quite a bit of mammary tissue. I did what your doc suggested: putting my finger over the outlet (luckily for me just one) and massaging toward the nearest breast as the babe nursed. The idea was that if there was any connection between the two, hopefully the milk would go that way, and, if not, it would dry up. It did after 4-7 days, I don't remember now, and it wasn't any more painful than just being engorged was. I've been nursing for 7 months successfully, and I haven't heard from my 'left nipple' since.