No, you didn't do anything, leeneia. But your email address is in the computer of someone who made the mistake of opening that file. The worm took all of the addresses it could find and "spoofed" email by saying it came from you or others in the infected computer's address list. When that infected email was received by Hallmark (another address in the infected computer), Hallmark rejected it with a message to whoever "apparently" sent it.