Make sure they test you for Whipple's disease that's all undigested minerals in your stool you can see all the different colors glowing off of it from the light. Also the iron you're taking isn't getting absorbed and that's why its so dark that or it's old blood coming out. This bacteria feeds off of iron be careful the iron could be making you worse I'd stop it if I were you. I stopped all vitamins because if they aren't getting absorbed properly then its just going to get deposited in stool or tissue or worse organs. I use to take prenatal vitamins and I think that's what caused my illness to progress quicker. Iron loading blocks your bodies natural defense to break down harmful bacteria in the intestines. Any kind of heavy metal loading is not good. Look into some chelators they will make you feel better. I bet you have a build up of porphyrins in your body from it too just like me. Be careful with high protein high acidic foods they increase porphyrin production. You might want to have your liver checked. They severely damage the liver and kidneys and neuronal pathways. Damaging nerves throughout the body including your brain. Hope this sheds some light on it for you. God bless you.