It's just the way the program works. Say something is currently at $20. I REALLY want the item, so I bid $110 on it. The bid will change to $20.01 (or maybe 20.50, or 21, I forget exactly how ebay does it)... not $110. Now wolfdog comes along and bids $25... since that is less than the $110 I bid, ebay will automatically bid on my account and place a bid for me at $25.01. The days go on and it gets bid up to $100... ebay enters $100.01 for me. Now the auction is almost over and at the last second, someone bids $110.01. That is higher than my bid.... so I lose the auction and they win it.

What I don't understand is what you mean when you say "check the bids and I'm currently the highest".