For the last 2 days, my email has been spamming my contacts.  I have now changed my password and deleted all of my contacts, but it is still happening.

I have noticed that the emails say that they are from my email address, but don't have my name written the same way as when I send emails from my account.  As well, they are not showing up in my "sent" folder.

This is all leading me to believe that the account has been hacked and my contact list stolen, but that the emails are now being sent from another server.  Is there anything I can do to stop this?