2 Things :
Theory : Riot is still testing their ranked system because even high elo players have played their smurfs and gotten Iron 4, it's somehow very common. Don't worry about it too much. Normally you only get your ranked placement when you do ALL of your 10 ranked games, so I think this is, again, testing their system on a wider range of people.
It's currently preseason so your rank will get reset when it begins in Jan/Feb (I don't know off the top of my head). Whether or not that will place you back into Iron 4, that's beyond me. I will say though, in my experience with Smurfing (As unpopular is it is), the system will initially base the hidden MMR starting point off the Normal Games that is then carried into Ranked Games when I decided to do my placements and get placed in mid elo rather than start from the bottom.