Why do so many people feel George Zimmerman continued to follow Trayvon?

I don't understand why so many people feel that George Zimmerman continued to follow Trayvon Martin after the dispatcher asked George Zimmerman if he was following the person.

George Zimmerman's initial written statement to the police shortly after the shooting:
http://www.gzdocs.com/documents/statements/written_statement_0226.pdf

In the non-emergency call regarding a suspicious person in an area where there had been some burglaries, George Zimmerman was sitting in his vehicle.  As George Zimmerman was speaking to the dispatcher, George is telling the dispatcher that Trayvon Martin was looking at him and heading in his direction.

At that point, George Zimmerman, while still talking to the dispatcher, gets out of his truck and starts to follow Trayvon Martin.  You can hear that George Zimmerman voice changing as it appears he could be walking at a fast pace.

When the dispatcher asked George Zimmerman if he was following the suspicious person, George stated yes, and the dispatcher told George "we do not need you to do that."

At that point, you can hear George Zimmerman respond "OK", and then you can clearly hear that George's voice returns to normal and no longer walking at a fast pace.

It appears George was heading back toward his vehicle as he tells the dispatcher where he will be located, and to have the police call him so that he can tell them exactly where he is located. George also tells the dispatcher that he doesn't see the suspicious person.

At one point Trayvon Martin came up on George Zimmerman asking him if he had a problem and punched George Zimmerman in the face knocking him down and began beating his head into the sidewalk.

George Zimmerman started screaming for help.  There is eye-witnesses that heard the screaming coming from George Zimmerman, while Trayvon Martin was on top of George Zimmerman.  Trayvon either saw or felt George's gun and they both struggled with the gun, with George shooting Trayvon.

If George was heading back to his vehicle, per the dispatchers instructions, then the pursuit of Trayvon Martin had ended.  It then turned to Trayvon pursuing George Zimmerman.  Trayvon attacked first, knocking George down, and Trayvon on top beating George's head.  George gained control of his weapon and shot Trayvon.

George Zimmerman's Speaks About Incident while taking a Voice Analysis
This video shows the size of George at the time of the shooting and he is not a very big man at that time.
http://www.gzdocs.com/documents/statements/video_interview_cvsa_0227.asf

The entire case that the State has against George Zimmerman appears to be that George Zimmerman continued to follow Trayvon. 

I admit, I didn't follow this case in the beginning when the news first announced the "Hoodie March" and the flashing of a very young picture of Trayvon Martin.  For a brief amount of time, I paid attention until a recent photo of Trayvon popped up and the video of Trayvon in the store.  I knew at that point, this case was going to get very ugly, and I didn't want to get "sucked" into this case, however, I did.

I decided not to watch what other TV shows with one-sided commentary were saying about the case, but to watch the motion hearings and stay focused solely on what the State has and what the Defense was presenting to the court.  Also what George Zimmerman stated in the non-emergency call, the initial written statement of what happened, as well as the interview where George spoke about the incident before taking the Voice Analysis test.

Monday, June 24, 2013, the opening statements begin and I am looking forward to what the State and Defense presents to the jurors.