You can easily track your transaction. Use a site like Block explorer. All you need to know is is the information about the Bitcoin address of the recipient and the amount of Bitcoins you sent. And you will see if your transaction is confirmed.
This is all that you can do with it. You can't take the money back unless the culprit is apprehended in real world, which is also harder because they might not be from your country. This serves as a lesson for you and everyone else, next time make sure that you get the product first especially if it is a P2P transaction.