Red or black poop could mean internal bleeding
Red means possible bleeding in the intestine and/or issues with the intestines, liver, or pancreas. Red or black poop can be a sign of bleeding in the Gastrointestinal tract and should not be ignored.
If you note this type of change, get to a doctor as soon as possible, even if it's temporary. Your body could be trying to tell you that something very dangerous is happening, and it needs help.