Breast soreness is a common complaint. There are many causes of this, some of which are worrisome and some of which are very minor. I would recommend that you discuss this with your primary care doctor
or OB/GYN. This can be evaluated, and likely treated.
Firstly, breast soreness is a common complaint. Many people worry
about this as they are concerned that it is a sign of cancer. While breast cancer is relatively common -- it is unlikely that this soreness represents cancer. Cancer rarely presents as soreness and rarely in both breasts at the same time. A painless lump is the more common presentation.
The fact that the breast soreness is related to your menstrual cycle is fairly common. As I am sure you are aware,the menstrual cycle is driven by changes in the hormones (like estrogen and progesterone) in your body. Breast tissue responds to these changes in the hormones -- growing and shrinking as it changes. It sounds like your breast tissue is responding to the hormonal changes and therefore causing some soreness. This is very common.
This can be treated. Often ibuprofen or motrin can help. If severe, taking birth control
pills to limit the cycle can eliminate this pain.
Talk to your doctor for more information.