so yesturday, i went to my sent folder and there were loads of weird mails which had been sent, to people i didn't even know or have added. i deleted them, changed my pw, and set my profile to private, i was going to delete my profile but i thought i'd ask here first.

today it's happened again, and i really don't know what to do. i don't have dodgy people added, only my best friends in real life. i checked comments in safe mode, and there were no embed codes or anything suspicious.
http://i7.tinypic.com/263abl1.jpg

it only started happening yesturday.
what should i do?

did you open any funky attachements or movies sent to you or in builitans?