How can I know when and where my card was redeemed
How to know where and when my card was redeemed
If you redeemed it onto your account you could try contacting iTunes Support and see if they can tell you when you did it : https://www.apple.com/emea/support/itunes/contact.html
If it was redeemed onto somebody else's account iTunes Support shouldn't be able to give you any information about it to due to legal/privacy reasons.
