My question is: I am afflicted with eating charcoal. Am I sinful?

If eating charcoal or other permissible things leads to harm, then the one who does so is sinful and must repent and stop doing it; because the Prophet, peace and blessings be upon him, said: "There is no harm or reciprocating harm," and because the author of Al-Maraqi said: "The origin of everything harmful is prohibition."