I get constapation then it goes away why is that?

Irritable bowel synd: You may have an irritable bowel syndrome, which manifests as irregular bowel movements , from constipation to diarrhea, to normal bowels. Also we know that our bowel movements are related to our life style, eating the right food, the right schedules, anxiety, fluid and fiber intake. Organise your life style, then see a gastroenterologist.