This used to happen to me all the time so I understand your anxiety. Same deal - fibrocystic breasts. I couldn't even do self-exams - well, I could, but it was pointless because I had so many lumps I didn't know which were routine and which were a matter of possible concern. Every mammogram - EVERY ONE - had some problem. Either they stopped me in the dressing area and said, "Come back for a better image" or they called me at home to come on back for some more "I'm sure it's nothing" moments. I've had a number of biopsies and one excision biopsy (surgery).
Just to balance it out, this often happened with my Pap smears too: "insufficient cells".
I did some things for breast health and eventually got rid of my lumps, and now every mammogram has been fine. But I well remember the many years when it wasn't.
Here's the thing - the new diagnostic machines pick up EVERYTHING. And the radiologists work with an abundance of caution. Maybe they don't want to get sued in this litigious society, maybe they just care about women. Either way, there are going to be more things that show up, and more things that require call-backs. Try not to focus on the few horror stories. Far more women are beating breast cancer than dying from it. Just look at the Relay for Life or Avon 3-day Walk photos, and you'll be inspired by the survivors. And I can't imagine where they could find enough space to hold a walk for all the women who got call-backs for a new image - there's no place large enough to hold all of us.
I'm hoping your situation will resolve quickly - and I'm sure it will!