How are you? It is always good to be vigilant with regards to our health. However, there are risk factors that make one more susceptible to breast cancer such as age, personal or family history of breast cancer, genetic predisposition, radiation exposure, early onset of menstrual cycle, first pregnancy at an older age, smoking, or alcohol intake (http://www.mayoclinic.com/health/breast-cancer/DS00328/DSECTION=4)
Otherwise, you don't have to worry at all.
There are plenty of women who experience the same worries and anxiety. It would be good to have a support group in your community or even in the internet that are in the same situation you are in and not compromise your love ones.
This is one link that discuss the breast and the diseases associated, both benign and malignant: http://www.ihs.gov/medicalprograms/MCH/M/MCHdownloads/Chap_P.pdf?page=2
I hope this helps. Take care and keep us posted.
Did you have a mamo done? I would do that to put you at ease.