The public address announcer blared, “The gold medalist and Olympic champion . . .” and that’s about the point that 17-year old Claressa Shields lost it. She started laughing uncontrollably before the announcer could even say her name. And once the medal was around her neck, she immediately clutched it, waving it from side to side and lifting it above her head. The excitement had taken over every nerve and every muscle.

“I thought I was gonna have a seizure,” Shields said later.

She laughed throughout the medal ceremony, after her 19-12 victory over Russian Nadezda Torlopova made Shields, a middleweight, the only American boxer at these Olympics — and the first U.S. woman — to win boxing gold. The whole time she kept grabbing at the shiny disc, making sure it was real and that it was really hers. Truth is, that medal might be the most believable part of Shields’s journey.

Her new prize, she said, is something she’ll wear every single day because it represents so much.

“I earned this,” she said. “This is my medal. I worked too hard. I worked really hard for this medal. I can’t even explain all the pain that I had went through, all the people I had to do deal with. And just life, period.”

Just a teenager — 165 pounds packed with personality, strength and charm — Shields has a lot of life experience behind her. Too much of it, really. She’s from Flint, Mich., a hard-luck town where every victory is a big one. She knows her parents, but splits her time living with an aunt and her boxing coach. Shields recently told Essence magazine that she was molested and raped by a family acquaintance when she was younger.

Her father served time in prison for breaking and entering, and she didn’t know him until she was 9. When he got out, Bo Shields, a former fighter, introduced his daughter to the boxing game.

At age 11, she wandered into a gym and met Jason Crutchfield, a journeyman fighter who made ends meet working construction. Shields picked up the basics quickly, and by time she was 13 — and women’s boxing was an exhibition sport in Beijing — Crutchfield began talking to her about winning an Olympic medal.

While Shields had a clear goal that she was running toward, she could never lose sight of what she was running from. In Flint, hope is a precious commodity.

“When I used to go running, I used to see all these crackheads, these drug addicts. I just didn’t want to be like them,” Shields said. “I didn’t want to be like them at all. I wanted to have a good life.”

Working daily with Crutchfield, Shields became the youngest boxer to make the U.S. team. Her family couldn’t afford to come to London, but her coach did. He helped guide her through the tough bracket.

Shields cruised the quarterfinal and semifinal rounds and went to bed Wednesday night knowing she’d face the talented Russian in the gold medal match.

She couldn’t sleep and kept asking herself, “Am I really fighting for gold?” She was out of bed at 5 a.m. Later in the morning, Crutchfield talked to his star pupil via Skype, bringing in Lissus Walker, Crutchfield’s old boxing coach, on a three-way call. It was barely 6 a.m. back in Flint, but Walker helped dissect the previous day’s semifinal bout and talked about adjustments that Shields needed to make.

Before they said goodbye, Walker asked the teenage fighter, “Can you do it?”

“Yes, Mr. Walker,” Shields said. “I can do it.”

At the arena Thursday, she didn’t even notice one of the loudest, most raucous crowds at these Olympics, which cheered Ireland’s Katie Taylor to victory in the bout that directly preceded Shields’s. Shields instead listened to music and waited for the bell.

Each fighter was able to sneak through some clean shots in the opening round, and judges scored the first two minutes even, 3-3. Shields was more active in the second, utilizing her jab. As Torlopova appeared to slow in the third, Shields remained the aggressor and added to her lead. Shields closed out the victory with a decisive final round and knew when the referee raised her hand in the air that everything had changed.

After disappointing performances by the U.S. men’s boxers, Shields performance was one of the few bright spots at these Olympics, the first in which women’s boxing was considered a medal sport. “I don’t think there’s gonna be anybody who watched the Olympics saying that women can’t box,” Shields said, “because they seen me get down.”

She tried to guess how life might be different now: History will remember her, she figures, and people will see her as an inspiration. “I might have 10,000 followers when I get back on Twitter,” Shields said.

She’s already noticed people poking their heads up from Flint’s cracks. Shields says she’ll be cautious.

“I’m not the type to bite my tongue for nobody. I’ll tell them, ‘Where was you at when I needed my hair done? Where was you at when I needed some money? Where was you at when I needed some clothes?’ ” Shields said. “You got to recognize real. I recognize real.”

Shields will begin her senior year of high school soon and says she doesn’t know whether she’ll try to defend her Olympic title in 2016. There has never before been a U.S. female gold-winning boxer, and she doesn’t know what opportunities might come along.

“I want it to be where my sister, my little brother, my mom and them, they would never have to go without a meal again,” she said. “I went without a lot of meals growing up.”

She stood on the podium Thursday night and couldn’t let go of that medal. It’s a symbol of what she has overcome, but also a promise, she hopes, of what’s yet to come.

“There’s a lot of stuff that’s going to be able to help my family out,” Shields said. “I got a gold medal that I can wear every day, by my choice. And it’s mine.”