More from John Green's 60 Minutes interview

John Green faced an adolescence of bullying and anxiety. But as he tells 60 Minutes correspondent Jon Wertheim, he turned his past struggles into a strength, creating a voice that resonates with teenagers today.

"I think in some ways I'm writing back to my high school self to try to communicate things to him, to try to offer him some kind of comfort or consolation," Green told Wertheim on the broadcast.

Bullied in middle school

Green understands how it feels be on the outside. In the clip above, he told Wertheim that he was bullied in middle school because he didn't fit in, an experience that made him feel isolated and scared. For him, being bullied was out of his control — and he didn't know how to make it stop.

"I couldn't fix the fact that I was a huge nerd, and I couldn't fix the fact that I didn't know how to talk to people in a way that made them life me or made them accept me," Green said. "And it felt like a math problem that I couldn't solve."

Rejected in college

By the time he got to Kenyon College, Green was working toward becoming a writer. But he told Wertheim that he was rejected from an advanced fiction writing class at Kenyon.

"For a while after that, I thought, you know, maybe if you're not one of the 12 best writers in your class at college, can you make a go of it?" Green said.

Advice from a writing professor changed his mind — and his writing style. Green's professor told him that his writing style sounded like someone else, not the way he told stories in person. Why doesn't he write the way he tells stories from his life?

Green said he still tries to apply this advice in his writing today. "It really stuck with me," he said.

"I realized I wasn't ever going to be a minister"

After college, Green knew he wanted to write — but he felt he needed to have a day job. For a time, he thought he would become a minister because he was interested in big-picture questions about suffering and meaning. He applied to the University of Chicago Divinity School, was accepted, and became a student chaplain at a children's hospital.

That's when he realized it wasn't the job for him.

"I didn't have the strength of faith necessary to withstand the stuff that I saw there, you know, to withstand seeing children die and seeing children die needlessly," he said.

Although Green said it was one of the most difficult experiences of his life, he took away something lasting from his short stint as chaplain. He began to write about kids who are chronically ill — a topic he would later explore in his hit novel "The Fault in Our Stars."

The videos above were originally published on October 7, 2018 and were edited by Sarah Shafer Prediger.