Stona threw an Olympic record of 70.00 metres -- just three centimetres farther than Lithuania's Mykolas Alekna.
"This is what I've been preparing for," he said. "This is what I dream of. To come here and actually do it, it's one of the best feelings of my life. It's the best day of my life."
But the 25-year-old said he was undecided on his sporting future.
"I'm going to sleep on it," he said. "I'm going to see what happens."
Stona has had tryouts for hopefuls at NFL teams the Green Bay Packers and the New Orleans Saints.
"It was very new to me. I knew the Olympic Games were coming up," he said.
"I've got a lot of thinking to do and do a lot of decisions to make."
Stona said field events should be more high profile in a sport in which track events often attract most of the attention.
Michael Johnson's lucrative new athletics circuit, being launched in 2025, will only feature track events.
"Field events should get more attention, to be honest. When I see something like that, it kind of de-motivates us," he said.
"We're putting in a lot of work as well, if not more. It's not easy. What we do is very repetitive. We've got to do a lot of maintenance.
"Everyone has to work hard but we've got to live with the playing field. Do you want to keep throwing or do you want to play American football? It's a great question."
