Terribly painful boob

Gemma
Hi there! I went to work yesterday and when I got home last night the usual tender breast sensation was present. But my right boob felt more sore, and there's a small lump that is new inside but near my aereola. (Spelling??) I don't know whether to go to the doctor, or whether it is probably just my boob doing the pregnancy thing, changing, being sore and possibly creating more tissue?? Anyone has this before?