I regularly have constipation for 7 to 10 days, and once i do have a bowel movement it is either diarrhea or has mucus. what could be causing this?

May be IBS?: Inflammation, infection ; ibs may be associated w/ abdominal discomfort, altered /alternating stool pattern, accompanying nausea, bloating, gasiness. Often improved by stooling, ibs is defined by changes in perception of gut distension, motility, sensation. Diet ; emotional stress play significant roles here in patients with ibs, but first need to rule out inflammation, ischemia, ; infection.