Hello! I will be assisting you today.
When you initially took the iron supplement this was due to a documented lab finding that it was needed and so the iron you took was absorbed by the body probably almost completely. Since the body needed it there was none eliminated in the stool hence no iron smell.
If you are now smelling iron after taking the supplement this simply indicates that there are significant quantities of iron in the stool from the supplement you took and the body didn't need.
It can take some time for the iron excess to be totally eliminated from the system and so the stool will retain this smell until the iron is cleared. This can take a couple of weeks.
If you have blood in the stool this would indicate a problem that would need to be checked out.
With you taking the iron supplement and now having iron smelling stools several days later this would be a normal finding.
You are very welcome!