This has likely happened because a spammer has forged (or spoofed) your email address as the FROM address on spam and you are the recpient of the bounce back messages. The important thing to know about this is that anyone can forge anyone else's email address. It's the digital version of forging a return address on an envelope. Your email account has not been compromised and these messages weren't sent from our server. Because of those two facts, you have almost a zero chance of being blacklisted.
Another important thing to know is that anything peculiar on Spam is intentionally meant to confuse you because spammers are con-artists at heart.
The most frequently asked question when this happens is: Can you do anything to stop it? The answer is no. Because the emails aren't being sent via our servers, we can't prevent them. The bounce backs will stop and the spammer will move on to forging someone else's email address. Adding spam filtration may block these bounce back messages, as the content of the messages will be what is typically considered spam.
The hows and whys of email spoofing are explained clearly and in detail in this article: http://www.windowsecurity.com/articles/Email-Spoofing.html (external link)