Yeah, you must have been hacked. But sometimes, when I check my email, I sometimes see my friends sending ads and spam. I don't think they would do that, so I suspect the companies who own the ads must have used my friends email to enter my Non-spam section in my email. But maybe I'm wrong. Maybe my friends are just real a**holes and are working together to get back on me for screwing their girlfrie-- opps.... I got carried away.
But yeah, you must have been hacked.