Having sharp pain in lower left abdomen, what could it be? Pain has been going on off and on all day

Constipated? Diverticulitis: inflammation of a diverticulum, esp. In the colon, causing pain and disturbance of bowel function crohns disease: chronic inflammatory disease of the intestines, esp. The colon and ileum, associated with ulcers and fistulae. Kidney stone: a hard mass formed in the kidneys, typically consisting of insoluble calcium compounds; a renal calculus. Ectopic pregnancy, ulcerative colitis.