"I'm really proud," LeeAdianez Rodriguez-Espada, who started running two months ago, said

A 12-year-old girl who thought she had signed up for a 5K ended up running all 13.1 miles of a half-marathon.

LeeAdianez Rodriguez-Espada of Rochester, New York, rushed to a starting line Sunday morning, thinking she was arriving late to the 5K for which she had been training, 13WHAM reports.

“The man told me I could jump in with his group of runners,” she told the news station.

So, LeeAdianez, who goes by Lee, joined the group and started running – only realizing something might be off after completing four miles – nearly one mile more than the 5K she was intending to run.

When she asked another runner how long the race was, she quickly realized what had happened. “That’s when it struck me that I was in the half-marathon instead of the 5K,” she said.

Her mom, Brendalee Espada, had been waiting for her daughter at the finish line, and began to panic when there was no sign of her two hours after the race began. She asked Lee’s friends to help look for her and even notified the police.

“I started crying all over,” Espada told ABC News. “It was really scary.”

In her final few miles, police spotted Lee and told her that her mother was looking for her. She had already decided she had come too far to stop. “She just wanted to finish the race,” Espada told the Democrat & Chronicle.

Espada cried as her daughter crossed the finish line, sprinting to the end to give her mother a hug.

“Then I see her with a medal and I thought, ‘Oh my gosh, she ran the other one,’ ” Espada said. “She is just 12 years old and she decided to just keep running and not [give] up.”

Lee told the news station that she started running just two months ago. She finished the half marathon in 2 hours and 43 minutes. “I’m really proud,” she said.