Sore nipples is one thing, but to HAVE a sore is probably something else.
Is your DS on AB's, or has he been?
I've currently got a section of areola covered in small blisters and feeding from it hurts like hell. So, I haven't let DD feed from it today - which I'm gonna have to deal with, but can't stand the idea of the suction of the pump! Might have to hand express.
I'd go see a GP about it, to take a swab and have it tested.
He has been on ab's, and onto a second course. It isn't a sore as such, but a really sore tender area. Almost like I've been hit there really hard and the pain just hasn't gone away itms
Will mention it to my GP next time I see her, or my OB if I see her first