"Everyone's so happy. It's pretty unbelievable but we worked hard and I think we deserved the win," Billingsley said.
"The boys all backed each other and the coach backed us and I think we knew we were going to do well."
Billingsley played a big part in that and some of the youngsters that he coaches were in the stands in Wellington.
"It's good to show them what can happen if you keep practicing," the forward said.
"I'm very happy. If I was going to score a goal, I'm very glad it was here in front of all my family and friends."
At 1-0 down after 30 minutes, New Zealand looked at sea but they were able to get back in the game, via Billingsley, and they ran Myanmar down in the second spell as their superior conditioning shone through.
Five players got on the score sheet at a venue that holds a special place in New Zealand football folklore courtesy of the All Whites' previous exploits.
A round of 16 game, which could likely be against either Portugal, Colombia or Ghana, would represent a noted rise in class but New Zealand coach Darren Bazeley welcomed the opportunity.
"Whoever we face now is going to be a massive, massive challenge," Bazeley said. "It gets harder, it doesn't get easier."
Bazeley made five changes to his side last night following their 4-0 loss to the US on Tuesday and that competition helped New Zealand thrive. Striker Joel Stevens, who Bazeley said was disappointed to have been relegated to the bench, came on and scored the Junior All Whites' third goal in the 78th minute.
Ukraine, who drew 0-all with New Zealand in the tournament's opening match last Saturday, top Group A with seven points, after they beat America 3-0 last night; the US are second. Myanmar finished last in the pool in their maiden appearance at the tournament.
Midfielder Clayton Lewis won't be available for the round of 16 if New Zealand were to progress after he picked up his second yellow card of the tournament last night.
New Zealand 5 (Noah Billingsley 40, Monty Patterson 47, Joel Stevens 78, Sam Brotherton 81, Clayton Lewis 89) Myanmar 1 (Aung Thu 28)
halftime: 1-1