Dear caroline923, No call backs do not only happen with women with dense breast tissue. A call back can be for any issue that comes up on a screening mammogram that needs further assessment for clarification. It is not an unusual happening and many times a more focused look or use of a different type of test will help to determine if there is an abnormality and whether any further evaluation is necessary.
Is that they say in the letter? Not a single issue that can suggest what it may be? What two other supposed findings? If you still have to wait a while before getting the next round of tests, call them and demand for further information then post it here. The information in your post says nothing that would support and answer,
Call backs happen to many women, it is not only to those who have dense breast tissue. If you don't wish to call them and ask as said, then calm down and try to get busy with something that will take your mind away from fear. If you will only have other tests, scans or images then fine but don't take any decisions about treatments until you are well informed and have the necessary knowledge.
Regards.
Marylou_II