If you receive an email message addressed from your own email address that you did not send, the most likely cause is a spammer has simply placed your email address on both the From line and the To line of the email message.  It usually does not indicate that your computer has a virus.  That being said, we do recommend that you run virus protection software on your computer, just to make sure.  In most cases, however, the spammer is simply trying to get around the spam filter.  If you receive such a message, you should report the message as missed spam.

As a side note, we do not recommend adding your own email address to your approved sender list, because this is exactly what the spammer is hoping you have done when they send messages in this manner.