Michelle Obama Looks Back on the 'Panic,' Vulnerability & Gratitude of Her Record-Setting Year: 'Life Feels Different'

Michelle Obama‘s eye-popping 2019 included the record-shattering 11.7 million in sales of her memoir, Becoming, and a sellout book tour that saw 375,000 packing the kind of stadiums Taylor Swift or U2 might usually fill.

But the former first lady says she doesn’t feel like a rock star.

“If you saw me on most days, in my sweats or workout clothes, you’d see that I don’t make a very good rock star. Of course, life feels a little different than it did while we were in the White House,” Obama tells PEOPLE in an interview for the new issue, in which she is named one of PEOPLE’s four People of the Year.

If anything, Obama confides, she worried her book — and subsequent stadium tour — would be a flop.

“I still remember,” she says, “waking up in a bit of a panic the night before my first tour event in the United Center in Chicago, this huge basketball arena. Were people really going to come? Was it going to be any good?”

At that point, she was almost two years out of the White House.

“Here I’d been first lady of the United States for eight years, giving speeches in front of huge crowds, but this felt so different,” she recalls of debuting her intimate and revealing memoir and then talking about it onstage in arenas in 31 cities. (At each stop, she also gave away thousands of free tickets to charities, students and community groups.)

• Jennifer Aniston, Jennifer Lopez, Michelle Obama and Taylor Swift are PEOPLE’s People of the Year! For more from their revealing interviews, pick up the new issue of PEOPLE, on sale now.

“I recognize now that the memoir and the tour were really different than what I’d done before — I wasn’t promoting a policy or rallying votes; I was out there, alone, talking about my feelings and vulnerabilities,” Obama tells PEOPLE. “That’s enough for anybody to lose a little sleep.”

At the tour’s first stop, in her hometown of Chicago, Obama stopped first at her old high school to meet with students in one of her old classrooms. It was then and there that she began to feel gratitude for the experience that had only started to unfold for her.

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“I asked how many of these girls didn’t feel like they belonged in a room with me. Almost every girl raised her hand,” Obama recalls. “That’s been the most powerful part of the last year — talking with all sorts of young people about how the things that we think are our inadequacies are usually our strengths. The simple act of sharing our fears and vulnerabilities helps us embrace our own stories and recognize how much we share with one another.”

Indeed, she says, “Everywhere I went — from Detroit to Copenhagen, Vancouver to Atlanta — I saw this generosity of spirit: people sharing the truth of their lives, no matter how messy or imperfect, as a way to offer each other a little more grace.”