yea, thats not the way they usually work....
try again to make sure, if you wanna change your order you'll need to be quick...
did you use this contact form, did you use the correct e-mail addres?
did you get a confirmation e-mail that your message was sent?
(normally several minutes after sending the form, you get a confirmation mail sent to you that says they'll try to handle it within 10 days...)