Why do i have sharp pains in the middle of my upper back before bowel ? usually feel better after emptying bowel. left breast / chest also feels heavy

Bowel Pain: "referred pain" from intra-abdominal organs can be difficult to pinpoint, but "stretched" loops of colon, especially the horizontal transverse colon, lies next to the stomach, and if it is overfilled, may cause the symptoms you describe, which are relieved with emptying. You might want to consult a gastroenterologist if the problems continue, to investigate the source.

Worth checking out: If it's always been this way, you may just be "wired funny". If it's new or worsening, see your provider. If you have constipation or slow bowels, stool and gas can gather in the splenic flexure, where the colon makes a sharp right turn under the left diaphragm before dropping down the left of your abdomen toward your rectum & that can radiate up into your chest. But see what your doc says.