What Causes Soreness In Breast?

Hi,i have been having some soreness in my right breast and goes a bit under my armpit but there are no lumps and i'm a very nervous person and i'm afraid to go see a doctor but i was thinking that this could be from the underwire in my bra because it seems to be in that area on the side.I sometimes get panic attacks from always worrying about this and it could be from losing my mom to breast cancer a year ago.I am so paranoid all the time and i'm having a hard time worrying about this that it's starting to take over my life.Could this be dangerous?