Sybrina Fulton, mother of slain Miami-Dade teenager Trayvon Martin, held a news conference Sunday, March 11 at a Miami Gardens church for her son, who was murdered by a neighborhood watchman.

“I’m a normal mother. I just want justice for my son,” Fulton said at the conference. “My heart is broken. I keep thinking he is going to walk in through the door and the nightmare is going to end.”

George Zimmerman shot the 17-year-old Krop High School junior as he walked to his father’s fiancés home from buying Skittles and an Arizona drink. He first called police to report a “suspicious person in the area” before following the youth in his vehicle.

A dispatcher told Zimmerman to wait for a police cruiser, but he decided to take matters into his own hands by getting out of the car and pursuing the teen on feet.

ABC News learned a fistfight broke out and the youth got the upper hand on the 28-year-old suspect who outweighed the boy by more than 100 pounds.

Zimmerman than shot the teen in the chest claiming self defense.

The police department who responded to the situation has been mum. The family of the victim has questions and the department isn’t answering.

The family wants access to the 911 tapes, but police aren’t releasing the tapes because the investigation is underway.

Bill Lee, Sanford’s police chief, told ABC News, “There is evidence that George Zimmerman acted in slef-defense.”