I just had a mammogram done and doctor wants me to have more test. i have lost about 20 pounds since last year would that cause my test to be differe?

Breast testing: You did not mention your age, or your family history regarding breast disease. If you had a digital mammogram, and it was read as normal, the additional test may be an ultrasound test, to discover a lump felt in your breast which did not show up on mammogram. In any case, a loss of 20 pounds can certainly make it easier to feel irregularities in your breast.