2 weeks PP, lump on breast stings

Ruby

I'm not sure if it's the lump itself but my breast started to sting after either a feeding or pumped session. And now it just comes and goes when it wants *the stinging* it is right outside on the left side of my areola. Wondering what it could be? It's making me nervous ! I am producing 4 oz per breast if that helps pinpoint this annoyance... I pump every day.