Continouis soreness in my right breast only and i am not pregnant what are other reasoning for it ?

Get examined: Could be cyst, fibroadenoma, hormonal changes with menses, other breast abnormalities, including cancers (don't know your age, history, family history, etc). Make sure it's not muscular, it's truly breast tissue that is sore; sometimes nerve irritation, e.g. Due to shingles infection can cause breast soreness before (or after) the rash appears. See your doc.