I took triphalia to help me have a bm and my stool was pretty dark, could say black. i ate unhealthy food the past two days. should i be concerned?

Triphala: ... Is an herbal supplement which is intended for many different ailments. Side effects can include diarrhea, gas, and "stomach irritation." Since black stools can be a sign of internal bleeding, particularly when they are tarry or foul-smelling, I would discontinue the use of the supplement and seek immediate medical attention in an emergency room if they are still black. Good luck.