G.M.
Ouch! Is it possible your nipple was rubbing up against the pump flange?
Breastmilk does promote healing, so I would express a little and rub it into the nipple. Try to be topless or at least braless as much as possible. If you have to wear a bra then I would slather on some lanolin to keep the would from sticking to the fabric. Also slather some on when you have to pump. Nursing your baby should be a problem, as the nipple goes far enough back into their mouths that it shouldn't rub up against anything.