Your first clue: It's Sunday, the busiest day of the week for eBay. A 5-second snipe is almost certain to get lost in the shuffle and not be recognized by eBay in time to count. And that's what happened. On Sunday, especially and particularly Sunday night, always allow at least 15 seconds from the auction end for your snipe to have a ghost of a chance to get through. If the auction ends on the exact hour, quarter hour, or half hour, that is X:00:00, X:15:00, X:30:00, or X:45:00 allow another ten seconds on top of that. This is because eBay runs a bargain deal that allows sellers to select their listing time. So many of them choose the exact hour, quarter hour, or half hour that there's a monumental logjam of bids coming in all at once at those times. EBay's servers just can't handle all of them at once.
Incidentally, you don't know whether $5.01 was the winning bidder's max bid. All he needed was 50 cents more than the next highest bid to win. His bid might have been $10.00 for all you know, in which case you would've lost anyway.
Let me suggest you read some of the subjects in the Forum archives to pick up on things like this. But we're always here to help if you're stumped, so feel free to ask.
