Well I been sucker punched once actually. Some dudes mistaked me and my friend for 2 other guys. After I took a punch to the eye, I said "hey WTF!!", and they left us alone.
About 2 weeks later a guy took my beer, I decided to just leave it as is instead of making a scene. I went to the bar to order another. Then I felt something like a headbutt on the back of my head. I turn around and see the guy who took my beer. He then punched me in the face again. At which point I punched him back. Everyone at the bar suddenly moved over because I punched that guy. The doorman was there and everyone pointed at me, so they kicked me out. The doorman was cool though.
Since then I started doing all-round self defense and Jiu Jitsu and haven't got in a fight since.
I was actually willing to fight a group of 4 or 5 guys recently just for the hell of it. I was hitting on his girl and then they all started hating on me and I stood my ground. I was ready to fight just to test my skills lol, it was pretty fun making all 5 of those guys scared.
That was a while back though. I don't think I'd want to do that again, especially since I haven't trained in months
.