What can be the cause of constant stomach cramps for 3 consecutive days. No other stomach symptoms is experienced. Have slight headaches also appear?

Sure, but... ...We're going to need a little more help from you. We can have your answer if you tell us the location of your pain, its intensity, duration, timing (with meals, urination, stooling) ; accompanying issues like fever, tenderness, vomiting, bleeding, etc, ; circumstances (exposures, pregnant, stressed). Also, what tests have been done to exclude some possibilities?