Hi i work for a bank and before i can give you any information on what to do, i need to know is it pending in your account or has it come through completely. like if you were looking at your card holds is it listed their or actually showing on the statement?? If it is in your hold it should fall off tonight during your processing. As some companies will try and authorize a higher amount on your card (Like showing a tip say your bill was 43.00 and you see a 55.00 charge. once the item is charged to the account the difference falls off) If the item shows in your statement call your customer service line and let them know you show an extra charge through your account. Also if you are close enough to go in go to your branch and talk to them explaining the charge sometimes they can take care of it at their end. They may have you fill out a dispute. But you will be fine in the end. If you have any questions feel free to contact me as i should be able to help you in this area.
Good luck!