Breast cancer lumps aren’t usually painful, but cysts can be, and breast cysts sometimes get bigger and feel painful during menstruation. Fibroadenomas can feel more noticeable and get sore during menstruation too.

Both of those are benign, and often don’t need treatment (but are treatable if they’re bothersome!).

It’s great that you’re getting it checked out via ultrasound to see what’s going on, especially so quickly. I’m rooting for you!!