Northern Ireland's glory night in Belfast
Two goals from captain Steven Davis, either side of Josh Magennis' header, lifted Northern Ireland to a 3-1 win over Greece on a historic night at Windsor Park.
After leading the nation to their first major finals since the 1986 World Cup, O'Neill was quick to hail his players, telling Sky Sports 5: "It's an amazing feeling.
"We prepared the team well, there's no doubt about that, the players deserve an enormous amount of credit because they have to buy into that and we built a really tight unit in the squad.
"But that's down to the players. We've got confidence, we've got belief and that comes down to winning games."
O'Neill, whose side will finish top of Group F if they claim a point in Finland on Sunday night, also had warm words for his skipper Davis.
The Southampton midfielder opened the scoring by stabbing home in the 35th minute before heading in just before the hour mark to get the celebrations well under way in Belfast.
O'Neill said: "There's all types of captains, but for me Steven epitomises everything you want in a captain: he takes responsibility on the pitch, he drives the team forward, he's an example in terms of how he is as a professional, how he is as a person.
"I didn't expect him to score an 18-yard header if I'm honest, but I'm delighted for him to get the goal because in my opinion he's one of the most under-rated players in the Premier League, he's a top, top, top player and he showed that again tonight."