Don't be scared....it's not uncommon.
I have incredibly "complex breasts" - not large, but I have lots of little cysts and knotty tissue and so on...LOL when I get mammos, I always have to warn the radiologist - they just about hit the floor when they see the images on the machines. In fact, when I schedule a mammo, I always tell them "you might as well schedule an ultrasound at the same time - there's always something they want to check" that way I don't have to make two trips.
For the last 6 years EVERY YEAR I get a mammo, and ultrasound, and sometimes needle biopsies or have to drain cysts. Nothing has ever been the least bit worrysome - some people just have "noisy breasts" - (that's the phrase the technicians use). My mom is the same way - 25 years of this. Nothing ever worrysome. They just need to be careful.
So to answer your question - of course i don't KNOW it's nothing...but there are many, many reasons to repeat a mammo and/or do an ultrasound BESIDES cancer.
I am glad you are now establishing what "normal" is for your breasts....it will help them tremendously as the years go by so they can track changes and note anything that breaks the pattern. The better they know YOUR particular breast tissue (which may have some inconsistencies just naturally), the more accurate they can be in identifying any problems early.
