Hello dear I understand your concern Lump below the nipple could be a breast cancer mass, fibroadenoma, cyst, breast abscess. Solid, multiple, movable and nodular mass suggestive of broadminded. Single solid nodule, fixed could be a cancer I would suggest to consult the surgeon for better management. Undergo following investigations: Breast examination, USG scan and USG guided FNAC (cytology). If above report is not conclusive then excision biopsy is the best. Fibroadenoma can be regressed by birth control pill and estrogen receptor modulator. Other treatment will depend on the cause. Take ibuprufen for the pain Hope this may help you Contact HCM for further health query best regards Dr. Sagar