Pending charge on my account

Follow the steps in this article:

If you see apple.com/bill, itunes.com/bill, or an unfamiliar charge on your statement - Apple Support

It is also possible someone closely related to you have had your card added to their account you can have them check their own purchase history to see if there is any matching charges:

View your purchase history for the App Store, iTunes Store, and other Apple media services - Apple Support

If you still can't find out what made the charges,

Contact apple by this link.

or:

Contact Apple for support and service - Apple Support

Good luck!