I am sorry you are in this situation! Is there a cancer center near you, where you can go for a second opinion? You get to choose where that happens and I always suggest outside the local network if possible. Also please go to one of the breast cancer advocacy sites and you can gain a wealth of information there. Now to your primary question, calcifications might not be cancer. Calcifications can be pre cancer, and a cluster of them certainly should be looked at closer. Better to stop it before it has a chance to get started, if it is those kinds of changes. They frequently cannot answer that until it is under a microscope. Sadly this type of lack of communication is too common, I ask doctors to be blunt, it serves us both and builds trust.
This is just one place where you can read good information on line.
https://www.nationalbreastcancer.org/breast-cancer-support-groups