Hi,
The term "Crystal" is often used by radiologists when crystals of calcium phosphate deposits (calcification) are found in the breast tissue and seen on mammography or other type of imaging.
These calcifications could occur on benign growths like a breast cysts or fibroadenomas .
Since your radiologist has recommended a 6 months follow up it indicates that these calcifications are not suspicious to warrant a biopsy.
Breast pain is not usually associated with breast cancer, but if the pain is excessive, by all means seek a second opinion preferably from a Breast Specialist.
Best wishes..