If this dominant symptom of a frequent or continuous sensation or urge to have a bowel movement, is associated with some of the following symptoms: constipation, a feeling of rectal fullness, left-sided abdominal pain, passage of mucus through the rectum, rectal bleeding, and anorectal pain, you may have an inflammation of the lining of the rectum, known as proctitis.
Another possibility is having irritable bowel syndrome.

Visit your physician!