I think that's possible. I've thought a lot about when the gun came out. Zimmerman's brother said he had a holster at his waist. For Zimmerman's story to be true, he would have had to get the gun out while Trayvon was straddling him and beating him to the point that he was almost unconscious. I don't buy that.
I've read that Trayvon was found with his arms under his body, which also seems odd if he fell onto Zimmerman. He would have been shot while holding Zimmerman's head, if Zimmerman's story were true. How did Zimmerman get out from under him? And either someone let him change or he somehow didn't get blood on his shirt. Witnesses' statements also describe some odd behavior from Zimmerman after he killed Trayvon.
So much doesn't add up.
I know; that's why I'm so furious with the police (or their superiors) for not taking Zimmerman's clothes. That blood spatter evidence could help find the truth.