My cycle starts on the 15th of every month. my breast have been sore for about a week and it's not going away could i be pregnant and see signs early?

Maybe you need to: check for pregnancy. If first test negative, then check again in 1 week. It is always good to assume that you may be pregnant, since breast tenderness is one of the first signs of pregnancy. If both tests are negative, and you have a period, then you know you are not pregnant. Breast tenderness can also come from hormonal imbalance and overstimulation, or infection if it is just one breast.