Was my gmail account hacked somehow?

Suddenly, this week I began receiving over 100 "Undeliverable Mail" notices in my gmail spam folder. With some filtering I'd cut it back to single digits but some were still getting through. I also changed my password since it appeared like my account was sending mail but that didn't stop it either. I finally just closed the account and opened a new one. The scary thing is that the spams were notifications of undeliverable mail, suggesting a spambot. My pop3, hotmail and yahoo mails are quite normal. Although I think this was probably happening at the Google server level, I still scanned my pc with NOD32, Spyware Doctor, AVG Anti-Spyware and Spy Sweeper with no malware detections. So what do you think was happening? Thank You!

what was the address the emails were coming from? was it dodgy looking?

you most likely got spam-attacked by some lamer

If there is no spyware...then someone was most likely spam emailing you...that is very strange though..

AJ