Bidding on an item

[sclqa]

I was bidding on an item and was high bidder at the end of the auction.  There was NO reserve on the item.  I had placed  a rather high max bid to assure I would not be out bid and loose the item.   However, at the end of the auction the winning bid price was EXACTLY my very high and uneven amount bid and not the winning bid displayed on the auction page just be for the end of the auction.

My concern was that there there were NO other bids shown in the bid history between the my last high bid and my much higher maximum bid.   

How can an item be at, say $20. as the auction closes and seconds later be, say $200. with no reserve amount on the auction and no other bids shown in the bid history between the $20. bid I placed and my $200. max bid. 

It is, as if perhaps, some knew my maximum bid and that max bid was was placed as the winning bid. 
Could my account be hacked?  Is there perhaps an error in the auction sofware.  What could cause this?

I am getting ready to do this again and don't mind paying up to my high maximum bid, but not if there are no other bids between my last bid and my maximum bid.

Advise