Can you tell me what I was charged for on my account?

We are fellow users, so nobody on here will know. To view your iTunes account's purchase history (and family members accounts if you are a family organiser in family sharing) : See your purchase history in the iTunes Store on a Mac or PC - Apple Support

Or could it be : About payment card authorization holds in the iTunes Store - Apple Support ?

If necessary, contact iTunes Support. Scroll to the bottom of the page in the 2nd link.

iTunes Support

iTunes Support – world wide

If you see an unfamiliar iTunes Store or App Store charge on your bank, credit card, or debit statement - Apple Support