Lump in nipple

I'm 14, and a few years ago, I was probably 11 or 12 I found a lump in my nipple. I told my mom, and she said it was probably nothing and that she would be fine taking me to a doctor if I wanted but I never did, I'm too absolutely terrified of it being something bad. I just hoped that it would go away and now I'm here and it's still there. It hasn't changed at all but now I'm just terrified. I don't know how to push aside my feelings and just go to the doctor, I'm just scared I'll go and my life will be changed forever. Does this sound like something serious?? How can I push myself to go to the doctor??