Sudden sharp pains in breasts especially left

I've been having sudden sharp stabbing pain on/in the underside of my breasts. Most of the time it's in the left side and rarely it is on the right side. Usually if there is pain on the right side it is more throbbing and dull. Sometimes it happens when I'm stressed, but usually it's pretty random. Afterward the pain radiates through my back and is just a dull ache. I don't know if these next symptoms are related, but I've also been having sudden headaches that like my breast pain only last a couple of minutes and pelvic pain that once again only last a couple of minutes. Both like my breast pain are random, sharp and sudden, and happen on both sides, but mostly on the left. Can anyone help me out?

Additional Information:
Female, 19. I wear glasses so the headache shouldn't be linked to my vision. I'm about 175 Lbs, but I work out regularly and try to eat as best I can.

[kbond7]

I also forgot to add because this will probably help some, but recently my grandmother had breast cancer and died because she contracted pneumonia. My mother also had non cancerous breast tumors taken out about 9-13 years ago. Both my grandparents on my mother's side (since I know nothing of my father's family medical history), had high blood pressure and/or diabetes. So far I have normal blood pressure and have not been diagnosed with diabetes, but I'm really just worried about my family's history with cancer, especially breast cancer. I have performed self-breast exams and have not found any out of the ordinary lumps.