Mammogram showed abnormality. was told due to density unsure if cyst or mass. repeat testing in 6 months. is this normal protocol?

A step is missing: I think. If a mammogram reveals a density, it is important to determine where it is solid or cystic. A solid mass is more suspicious for cancer. That question can often be answered by performing an ultrasound exam. You don't give your age (perhaps waiting for this more acceptable in very young) but I would like the question of cyst vs solid clarified. Consider asking for ultrasound now. Stay well!