Pain in my breast, but no sign of breast cancer.what this pain should be?

Pain: Breast pain is mastodynia or mastalgia. It is very common in women & usually related to monthly hormonal changes or from hormone medications. It is common in fibrocystic breast condition. Need to be sure there is no cancer. Many sites list treatments of low fat diet, etc. See your gynecologist for treatment discussion.

Fibrocystic Disease: There are many causes of breast pain. Cancer is unlikely but a breast exam and mammogram are recommended, particularly if you have a family history. The most common cause is fibrocystic disease, especially if the pain fluctuates with the menstrual cycle. It is also important to rule out other causes as sometimes "breast pain" isn't coming from the breast.