My breast feel soar and sensative. already took a pregnancy test and im not pregnant. no lumps so i don't think its cancer. whats wrong?

Linked to periods: Often your breasts can become tender with cyclic hormonal changes in your body. You can take Motrin for symptomatic control. If it persists > 3-4 months, see a doctor for further evaluation.

Most likely hormonal: Near your menstrual cycle the breast may become sensitive. Other reasons may be caffeine sensitivity or mastitis. Depending on your age you may need a exam and or mammogram.