You will be charged when your order has been verified and approved.
The payment process happens in two stages; the first step is an authorization, this is a temporary hold of funds on your credit/ debit card, when you purchase a product using card payment, the bank will 'hold' money on behalf of Huda Beauty to ensure there will enough funds to be charged when the order is confirmed. This may reflect as a transaction on your account but at this stage no funds have been taken from your account.
The second stage of the payment is when the funds are transferred from your account. These steps usually happen within minutes of each other. However, if your order is not verified and approved, the funds will not be transferred from your account and the hold will be reversed after 48 hours. If this happens, you will receive an email updating you that your order has not been succesful and no money has been transferred.