“I’d probably make the same bad decision if some dude with an earring was following me around in his car at night and then got out of his car to pursue me on foot. “
If you start beating on someone, there is always the danger they are armed. Deterring violent attacks on people is one of the pluses of the right to bear arms. So my advice to you would be if a strange person is following you and they make you nervous, get to a well lit area with other people around. Attacking them is risky business.
Ultimately whether Zimmerman is in the wrong or not depends on whether or not he was attacked by Martin. If Martin attacked him first and was in fact smashing Zimmerman’s head into concrete, the what was Zimmerman suppose to do? If Zimmerman attacked Martin or physically tried to detain him, then the situation is certainly different. So far the police think the evidence points to Zimmerman being attacked including apparently an eye witness.
I agree with most of your post, and especially the bolded part. I think you're right that if Martin attacked him first then Zimmerman is entitled to claim self defense. However, the eye witness only saw that Martin was winning the fight. As far as I know, he did not see who started it. It's certainly possible that Zimmerman started something he couldn't finish.
I think this comes down to Zimmerman's credibility, which is best assessed by a jury of his peers that actually gets to hear what he has to say.
And even if Martin struck first I still think the attacks on his character are completely gratuitous. A lot of people in that situation would strike first.