I've had horrible cramping pain in my middle/upper stomach all day that radiates to my back. it feels slightly better when i lay down but otherwisebad?

Depends on history: Long list: Ado you get bad periods and are due, it may be that, endometriosis, urine infection, pancreatitis, ulcer, constipation, colon cramps, gallbladder problem. Worst case scenario is ectopic pregnancy, appendicitis. If you feel unwell, fevers, very severe pain, probably need to be assessed. If it is not improving or there are other symptoms of illness - SEE Dr.

Considerations...: Epigastric burning & pain after meals raises the probability of gastritis &ulcers. Stop any non-prescribed nsaid's or aspirin; cut out tobacco &alcohol; start an otc acid reducer. Seek emergency care if lightheaded, worsening symptoms, vomiting coffee ground material or passing black stool or blood. Pancreatitis/biliary pain mid-colon spasm, & heart pain can present in this way too. See UR doc pls