I have just received 2 tweets from myself but I didn't send them. Must be a virus. Anyone had this before?

[Oddblob]

First do exactly as answered earlier:
"You have allowed an app to post on your behalf.

so check what apps you are using,
both on twitter
also on facebook if you have it.
also check what apps you have allowed on to your Yahoo account
and any other such accounts."

Then, install a program called Malwarebytes Anti-Malware And start your computer into Safe Mode, and run the scan, the reason I suspect malware, is becasue I recently fixed my friends laptop from a social networking virus known as: Trojan.Zbot