I would not get too worried about this and yes, how easy for me to say that, isn't it? Mammography has a high rate of false positives, especially if your breast tissue is dense. I know many women who have had this experience and it was nothing more than calcifications. There are also a number of things that are benign in nature that will show up on one and you won't know until they do this further testing. I am sorry you are going through this because I am sure it is a very scary thing to hear. Deep breaths, deep breaths.......Get the other stuff done ASAP because you will be able to relax a bit more when they figure it all out. But many women have that second call and it proves to be nothing serious. I would not lie to you.
I still have to answer your thyroid post but my mother-in-law is here for a visit and I am busy. I will post a response soon!