It was a special moment for the Year 13 pupil, who showed plenty of emotion standing on stage as a haka was performed for her.
"I had my little moment before everyone came," Fairweather, 17, admitted.
"I was sitting in the foyer and I was like, 'Holy crap, I'm going to the Olympics, this is insane'.
"Then I composed myself a little bit more."
Fairweather has long been an impressive talent on the local and domestic scene.
But it was her efforts as a 15-year-old in 2019 that catapulted her on to the world stage.
She won a gold medal in the 200m freestyle at the junior world championships.
That came weeks after her first senior world championships, which included a race against American star Katie Ledecky.
Late last year she qualified for the Games in the 400m freestyle and obtained a wildcard spot in the 200m, having missed the automatic qualifying time by 0.1sec.
The Games begin on July 23.