How would i know if i have this fibroadenoma and is mobile lump possible for breast ca?

Not impossible...: Fibroadenomas are common. These are benign breast lumps, and are far more common than breast cancer in your age group. They are definitively diagnosed by biopsy, but ultrasound can give you a good idea that fibroadenoma is what you are dealing with. While twenty is extremely young for a cancer, never let anyone say you are "too young" for breast cancer. Check it out if you are worried. Lgromko md.

Lump: If you have a lump, and you are 20 years old, you need an ultrasound for better definition of the lump, followed by ultrasound guided biopsy to prove that it is only fibroadenoma, benign, and not something else.