Ebay doesn't enforce the rule about retracting your bid. If you entered the wrong amount, then you should make another bid with the correct bid. But no one does this. It is a loophole that ebay lets bidders get away with. IMO, you shouldn't be forced to pay since the retraction wasn't honestly done.
http://pages.ebay.com/help/buy/bid-retract.html#cond
You can retract a bid for the following reasons:
You accidentally entered the wrong bid amount due to a typographical error. For example, you bid $99.50 instead of $9.95.
If this happens, you need to reenter the correct bid amount right away. Changing your mind does not qualify as accidentally entering a wrong bid amount.
The item's description changed significantly after you entered your last bid. For example, the seller updated details about the item's features or condition.
You can't reach the seller by telephone or email.