Assume the worst. Push the red button. Go nuclear. Cancel your card immediately and get a new one, just to be safe. It's only a new number, but you could be heading off a great deal of trouble. If your card is compromised and you use the same PIN / PW for access with other cards (many folks do), you better start changing all your other cards. A bit of inconvenience now is far better than doubt and uncertainty for the rest of your life.

