All iron supplement s and salts colour feces . It's quite natural that your stools are dark. There's nothing to worry about.dexorange syrup is a iron supplement too.
Continue to take iron supplement under supervision of your doctor.
dark leafy vegetables, eggs, chana, Halim, sprouts, mutton,
liver, dark raisins, dates are good sources of iron too. include in your daily diet with some citrus fruits like orange, kiwi,etc