Hi Kelly,
Please remember that most breast lumps are not cancer. And breast cancer is far less common in someone as young as you are. That being said, it is always wise to see a doctor when you do notice a change in your breasts. Until you know for sure, please try and relax (easier said than done, I know). Try to keep busy (I found that really helped me).
Good luck and do stay in touch, OK?
Laurie