Bellingham, Washington (CNN) A 16-year-old girl agonizingly tried to save her step-grandparents after a fiery small plane crash into a Washington mountain last weekend, she told CNN.

Autumn Veatch described the chaos after the Beech A35 aircraft hit the side of the mountain on Saturday and her amazing two-day journey to rescue.

"I got out. There was fire. That's how my face got burned. My hair was burning. ... And -- my immediate response was to go and try to help them out. Because they were alive. They were alive. They were both screaming," she said.

Autumn said she realized that she couldn't get to her grandmother, Sharon Bowman, who was on the other side of the airplane. She thought if she could get her grandfather, Leland Bowman, out first, then his wife could follow them to safety.

She tried and tried, she said, until she realized there was no saving him.

"I was trying to pull him out and I just couldn't do it. There was a lot of fire. And I am a small person," she said.

The plane was found extensively burned when searchers arrived after making their way through the rugged, nearly vertical terrain, according to the Skagit County Sheriff's Office. The two bodies were still inside.

JUST WATCHED Plane crash survivor home from hospital Replay More Videos ... MUST WATCH Plane crash survivor home from hospital 01:53

Autumn hiked out of the rugged North Cascades Mountains on Monday, two days after the crash, covered in burns and bruises.

She told CNN she thought she was going to die of hypothermia.

"I was freezing," she said.

Autumn recounted how when she was a fourth grader she and her father used to watch shows about surviving in the outdoors. After deciding to head for help, she went downhill, a decision searchers say was a factor in saving her life. She could hear the sounds of a highway, but that faded. She knew she needed to find some sort of running water -- not only to drink.

"Water always leads to civilization," she said.

She came upon a stream, and followed the flow. It became a river, and on the second day it led to a bridge. She walked up an adjacent trail to a parking lot where there was one empty car.

She went back to the highway and stood suffering by the roadside, trying to get people to pull over, but cars kept passing.

Finally, after an hour, she went back to the parking lot, as she sat in the rain with her sweater pulled over her, another car pulled in.

The two men inside took her to a store in Mazama, near the Canadian border. They bought her a sandwich and one of the men called police. He handed her the phone and she described her horrific ordeal.

Autumn developed rhabdomyolysis, a muscle disorder, during her ordeal, but suffered no life-threatening injuries, said Scott Graham, chief executive of Three Rivers Hospital. Rhabdomyolysis is often caused by an injury that damages skeletal muscle, according to the National Library of Medicine. Fibers from the damaged muscle enter the bloodstream and can cause kidney damage, but recovery is possible with treatment.

She had burns on her hands and was also extremely dehydrated and exhausted.

Autumn had been visiting her mother in northern Montana when her grandparents offered to fly her home to Washington.

The flight from Kalispell became very cloudy and there was one near miss before the accident, she said.

Visibility went to near zero, she recalled, before her grandfather made the decision to fly higher.

She said she was hunched down and she could only see white as she looked ahead out the windshield.

Then it was light. Then trees.

"The impact itself didn't really hurt me. But the fire did," she said.

The first day was very difficult. She blamed herself for what happened.

"They mattered a lot to me," she said, even though she had only known them for a few years.

She cried a lot that day. Not only did she have the guilt of being the sole survivor, it was also raining. She was soaked. She tried to sleep near the crash site. She's not sure if she did.

Autumn said she thought about a text to her boyfriend. It was a joke she had written during the flight, during some turbulence.

She had written, "If I die, just remember that I love you."

Hours later, freezing, unable to feel her feet, feeling hopeless, she decided she couldn't die there.

Going down the mountain was tough. She had to cross the water several times to find ways to get through the thick woods. Twice she slipped on the rocks and tumbled into the frigid water.

And there were waterfalls. Rather than go over with the water at the first one, she scaled down a 20-foot wall in her Converse shoes, her sweater and her "burned-up pants." The next waterfall was only 10 feet down.

She slept the second night in a sand bank and woke up covered with bug bites.

"It's weird. I never thought I had it in me to go through all that stuff. I'm kind of a huge wimp," she said.

Autumn said that in the past she's also been a negative person. She's an introvert who struggled with depression.

"This really gave me a newfound respect for life," she said. "I have never loved being alive more."