Okay I guess you bought the Battlefield 4 PC version via our Origin store? You can and should check your Origin order history as well as your e-mails. You should got an confirmation about your purchase. It can take a while until your purchase went through, depending on your way of payment. Some payment options can take up to 48+ hours while credit-card payment is usually the fastest way to buy a game.
If you are sure that your payment was successful, you should update your Origin client and choose "Show: All" or "Show: Hidden Games" as view option in your library. If you game is still missing, I would recommend to get in contact with one of our Game Advisor. They can perform a further account check and have insight in your order history.
Cheers
Basti
