If that's what happened, then you need to inquire with EBAY. It has been my experience, that last second bidding generally outbids the person's max bid because the new bidder puts a unrealistic amount that forces the current leader's max bid plus the additional 50 or more cents.
Example: I am bidding on a chip at $4. With less than 10 seconds to go, another bidder uses one-click bidding and puts $20 in his bid box. What you see is you lost the bid by $4.50 in the final seconds of the auction. You don't see the second bidder placed a $30 max. It just shows you lost by 50-cents. That type of bidding could backfire on a bidder. I had several bidders on a NFL Super Bowl media pin that sold for $110.00. One of the bidders kept bidding, raising the leader's max bid. Was he surprised when the auction ended. Be careful if you use that type bidding cause it could cost you.
I hope this helps in some way.