What's wrong with it? Why would you want to sell it? If you bought it from a US carrier the time for return for a full refund should still be running.
That's not a decision that I, or anyone else on these boards can make for you. Why you would sell something (anything) is a personal decision.
Except for one thing: If this is your only ID and you really are so new to eBay that your feedback rating is only 1, I would warn you about trying to sell a "hot" item like the gold iPhone 5 on eBay. With high-profile consumer electronic items like new iPhones, an inexperienced seller is a target for buyers who will try to pull some kind of scam.
Watch out for the foreign bidders. ALso remember the ebay fees. The profit isn't going to be that huge due to the ebay fees.
Sell it! and then let us know what happened when it is over.