Welcome to NP!
The amount being deducted should be the amount showing on your invoice. You should have an automated email receipt for the purchase showing the amount you were officially charged, as well as an invoice you can view when you log into your domain registrar account.
Most bank accounts will show a pending status until the funds clear. Being the holiday weekend you may want to give it a couple of days, as banking institutions may vary with clearance times.
With regard to variance of price, if you were charged 9.99 as your post reads, then you should not see more than that amount being deducted, unless there was additional taxes or icann fees, etc. Check your invoice statement for the final total.
-Regards