What you are calling "taste" is actually produced by the olfactory sense – "smell." True taste, which requires contact of a substance with your tongue, is limited to sensations of sweetness, sourness, saltiness, bitterness, and umami. The chemistry of taste is certainly quite interesting, but anything beyond those "flavors" is produced by smell (via far more complex physiological processes). You have certainly smelled rust (or, more accurately, various oxidation states of iron that exist in blood, likely from wet or weathered steel). So you are, in fact, correctly associating the smell of iron oxides from two different sources: steel and hemoglobin.