Do you have the item number? If so paste it into the URL: ebay.com/itm/########### If a short form completed listing page comes up look at top left for the reason the listing ended. You can also click on the # of bid display to see if any bids were cancelled before the end. If the item number is not found, eBay removed the listing for some issue with the listing and/or seller (this also applies if you had the listing on your Watch List and it is gone from there).
If you don't have the item number rerun the search where you found the item originally and if it's not in the results for active listings click the box to show "Completed listings" in the left column of the search results.
I recommend you place any listing you are planning to bid on onto your Watch List (or another list you make for that purpose) BEFORE you bid so it is easy to find after you bid: you won't have to look in 3 different possible locations (Bids, Didn't Win, and Purchase History, and if your bid is cancelled it won't be in any of those even if the auction is still running, AND it can take some time after it disappears from the active Bids section at the end of the auction to show up in the appropriate other section) as it will be in the Watch List regardless of your status in the auction (unless eBay removes the listing).
