Hello from JustAnswer.
Bright red blood is a sign of bleeding either from the anal canal or low in the colon. Bleeding from higher in the colon would be a darker red, commonly described as maroon colored. If the blood is not integrated into the stool, that would also indicate that the bleeding is in the anal canal or very low in the colon.
The most common cause of bright red blood when you have a bowel movement are benign anal conditions, such as hemorrhoids or anal fissures. Hemorrhoids are dilated veins that can occur inside or outside the anus, and the external hemorrhoids can be felt, so if you do not feel anything, it could be an internal hemorrhoid. An anal fissure is a superficial tear along the lining of the anal canal. Both of these conditions can happen secondary to changes in bowel habits, and could be related to the efforts to clean the colon of stool. Both hemorrhoids and anal fissures are problems because they cause symptoms, but they are not otherwise serious conditions.
However, there are some other conditions that can cause bright red blood in the stool that are more serious. This can include inflammatory bowel disease, diverticular bleeding, vascular abnormalities, or growths in the colon. The growths can be benign, such as polyps, or malignant, such as cancer. However, the level of concern about growths would be greater as you get older.
Pain can commonly occur with hemorrhoids or anal fissures, although typically limited to the anal area. Abdominal pain may still be related to retained stool, but also can occur with some of these conditions that cause blood in the stool, such as inflammatory bowel disease.
Generally speaking, we prefer to perform an exam or tests to find the cause of the bleeding. Anal problems can usually be diagnosed in the office without special procedures, but examining the lower colon would usually require a scope procedure. So, it would be better for you to see your doctor about the blood in the stool. It is not an emergency, so it would be fine to wait until you can contact the doctor's office.
Until you can be seen, since it is most likely a hemorrhoid or anal fissure, it is reasonable to use over the counter medicines for hemorrhoids that can help either condition, such as a hydrocortisone hemorrhoidal cream. It is also reasonable to continue efforts to empty the colon.
If I can provide any additional information, please let me know.