nipple lump

I am 16 years old and I have a painful knot under my right nipple? I have had it for as long as I can remember, but it has grown and has become painful for the last few weeks. Should I be concerned?

[Cleveland Clinic]

Dear willy620:  It is not unusual, particularly in young women, for breasts to feel lumpy.  Further, these lumps can sometimes swell and become painful, especially during certain times in the menstrual cycle.  Most breast cancer is not painful.  If this lump is, in fact, growing, you should have it checked out by your doctor.