One of my breasts, sometime both get sore at the top of my breast. The soreness is close to the beginning of the bra strap.

My bra is not tight. Also if I rub the area it seems to hurt more. It doesn't matter what time of the month I feel this. It just seems if I touch myself in that area I can feel slight pain or pain with burning. I don't drink alot of coffee, tea or alcohol. Or eat alot of chocolate. Had mammo Mar or Apr 2009 with sonogram and everything was normal. Should I be worried?