"Every fight I'm really nervous, but this fight, it was either I go to the junior worlds or I don't - and I wanted to go," she says.
It took several hours for her achievement to sink in.
Encouraged by her mother, as were her three brothers, Dylan, Jordan and Brayden, Brooklyn started Taekwondo as an eight year-old.
She is a member of the Budo South gym based at Greerton and also trains at, and is sponsored by Fitco 13th Avenue, which is owned by Taekwondo New Zealand development officer Tim Urqhart.
Brooklyn works at the gym as thanks for the sponsorship. She trains six, sometimes seven, times a week.
She won gold at the 2014 New Zealand national championships, gold at last year's New Zealand open, gold at the Gold Coast Open in 2014 and two golds at the same event last year.
"Mum pushes me and I like to know I'm getting fitter and better," she says of her motivation. "And representing my country, it's pretty good to be doing that as well."
Getting focussed for a fight is crucial.
"BeforeIgo on, the only person I can talk to is my coach and if I'm not fighting, I try and keep my mind off it. But going into the ring, it's down to business."
Brooklyn has become known for her scream. "It puts people off and gets into their heads," says Hayley.
While this weekend's camp is in Hastings, Brooklyn travels to Auckland most weekends to train with New Zealand coach and double Olympian Robin Cheong and current Olympian Andrea Kilday, who will be New Zealand's only Taekwondo athlete in Rio later this year.
Hayley was team manager at the last world junior championships two years ago in Taiwan.
"It will be nice to have one of my children in the team. To see your child representing her country - it's a pretty special moment."
The New Zealand team for the junior worlds includes nine males and five females plus officials.