Can anyone tell me what could be causing both sides of my breasts to hurt and for it to go under both breasts towards my spine?

Several answers: If you have had abnormal periods lately, your breasts may be responding to a change in hormones. Breast pain can also be "referred" from the esophagus, stomach, liver, duodenum (small intestine), liver, and gallbladder. It is very common for gallstones to give pain like a "tight band" around the lower rib cage or bottom of breast, and to spread around to spine or between shoulder blades. See Dr