Not to worry you all, but some breast cancer IS painful. Don't let the doctor's tell you otherwise. I speak from experience. I had a painful lump and just KNEW it was cancer. I went to numerous doctors, all of who said....you're too young (I was 32), you have no family history.....breast cancer isn't painful..........it's just fibroids.
I was not satisfied with those answers. After becoming proactive in my own health, 7 doctors later, I found a doctor who actually listened to my concerns. Did a fine needle biopsy....the results were "suspicious tissue" I was then sent for a biopsy that revealed that I did indeed have Stage 2 carcinoma in situ. On July 17 I had a bilateral radicam mastectomy and subsequent reconstructive surgeries. That was 10 years ago.
As I said, I am not here to frighten you, just to show you that your health is in YOUR hands. Find a doctor who will explain things to you in a way that you will understand and that you are comfortable with. If you are still unsure, get a second opinion, heck a third if you have to, I went so far as to have seven.
I would, in all likelihood, get a second opinion if I were you.
**EDIT** I am NOT in any way shape or form suggesting that you may have breast cancer, that is not my intention here. My intention is to show you how powerful you can be regarding your health. I am attempting to show you that not all doctors know everything and that sometimes it is imperative that we seek out advice from other medical professionals.