ST. PETERSBURG (CBSMiami/AP) —  The parents of a Florida teen who shot a police officer then was fatally shot say he suffered from mental illness but never got a specific diagnosis.

For a short time, Austin Goodner took medications to treat attention deficit hyperactivity disorder, schizophrenia and bipolar disorder, but doctors could only determine that he suffered from “a possibility of this, a possibility of this, a tendency of this, a possibility of this, a little bit of that, maybe we should look at that,” Diana Goodner, his mother, said Friday in an interview with The Tampa Tribune.

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St. Petersburg Police say that on Sunday, the 18-year-old argued with four people near a city pool, shot a man on a bike in the arm. Diana Goodner said her son called her for a ride home Sunday after he had been fishing, and he didn’t tell her about the altercations or that he had a gun.

That evening, when police arrived at the Goodners’ home, the teen came outside and shot Officer Michael Cordiviola in the leg. Other officers returned fire, fatally wounding him.

The teen was known to officers, having been involuntarily committed twice in 2011. He had also been previously arrested for aggravated battery.

“He’s not a cop killer,” said Noah Goodner, his father. “He just wanted his own life to end.”

The couple said they noticed a change in their son when he was in the third grade, but he didn’t want to speak about his struggles as he grew older. They said Austin Goodner had a passion for animals and wanted to work for the Florida Fish and Wildlife Conservation Commission.

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Diana Goodner said while the family still has questions about where the teen got his gun, the family took some comfort in his final words, expressing love for them.

“There’s a fresh feeling that we have. The demon that landed on Austin is gone,” she said.

Cordiviola was released from a hospital Tuesday. After he was shot, he fashioned a tourniquet from a nearby garden hose to stop the bleeding, while he department-issued combat tourniquet was yards away in his patrol car.

Chief Tony Holloway tells the Tampa Bay Times that some officers had complained that the $30 tourniquets distributed to them three years ago were too bulky to carry on their belts. St. Petersburg officers are required to have the tourniquets readily accessible, but they don’t have to carry them.

Each officer now will be issued a supplemental tourniquet that folds more easily into uniform pockets, police officials said.

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