Hard lump on rib above my breast. first noticed 2 wks ago. i think it has got slightly bigger. seen doc. u/s clear, waiting x-ray. any ideas?

Breast nodule: The mass is likely in the soft tissue rather than the rib. This may be fibrous breast tissue which can worsen with caffeine intake and can be associated with menstrual cycle. At your age, you should have a baseline mammogram and your physician should discuss any family history of breast disease. Breast MRI may be necessary if all other imaging modalities fail to isolate the area.