Yes, Christine, I have. I had to have follow up this year after my very first mammogram. Scary! they told me they could see calcifications on one breast and wanted to retake the images in 6 months. Apparently calcifications can alter the cells around them which can be the start of cancer, I think that's what they said, so they wanted to check up on this. I went back and it was fine and I will go back again in another 6 months. try not to be scared. It's good to have things checked out, just to be sure. And if, like me, you have dense breasts, it is hard for the radiographers to read the image for problems, so they often do call backs to get clearer images.
Hope this helps,
Clare