From: addresses on spam are ALWAYS forged.

The From: and To: addresses are chosen randomly from list of email addresses that were harvested somewhere. The fact that you appear to gotten mail from yourself is most likely a coincidence.

If you post the full rfc 822 headers I can tell you for sure.

Still, it pays to be careful. I use firefox with ad blocking and scripts disabled. The family computers are set up with antivirus, antispyware and antiadware software (all free BTW). All the computers are also behind a firewalling router.