I had a black stool yesterday and i knew because i ate black licorice and iron pill. so i stopped eating it but until now i still have a black stool ?

Not normal, get help: Blood in stool is a warning sign. Brisk bleeding warrants emergency care. Causes of bleeding may be predictable (e.g. rectal trauma), but evaluation is always appropriate. A rule of thumb (but not absolute): black stool means bleeding comes from upper GI tract; grape jelly stool from small bowel; silver stool from biliary tree; burgundy stool from right colon; red blood from left colon to anus.