The 17-year-old DeLand boy, whose name was not reported, took the drugs with friends Tuesday, the Orlando Sentinel reported.
When his friends left him, he fell asleep, only to wake up a short time later thinking he was in a dream.
The teen told deputies he felt like he was in a nightmare and could not escape his house. He said he then went into his parents' bedroom, found their .22-caliber rifle and shot himself in the forehead.
"I just wanted to wake up from the bad nightmare," he said.
Still feeling stuck in the dream, he attempted to clean up the blood spatter and bandage his head. He then went outside and found someone to drive him to a hospital.
The teen told deputies and emergency room staff he was not trying to kill himself.
"I'm happy and I love my life," he said.
Volusia deputies said the teen will not face criminal charges.
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