Chances were at a premium at Windsor Park as both defences came out on top.
Patrick Kelly hit the crossbar in the first half for Northern Ireland, and Isaac Price had an effort beaten away by Balazs Toth.
After Dan Ballard controversially conceded a penalty in Georgia, Shea Charles also had a penalty appeal waved away in the lead-up to the Kelly chance for a similar incident.
While O’Neill said he had yet to see it back, he did quip that “the referee never seems to make the walk for us to the side of the pitch. It never seems to happen for us.”
The threat of Liverpool midfielder Dominik Szoboszlai was largely nullified throughout the game as Hungary, like Northern Ireland, struggled to create any clear-cut chances.
The only save that Pierce Charles had to make in goal was when a lethargic clearance led to Alex Toth shooting towards goal in the closing stages, but the QPR stopper was otherwise untroubled.
After a 5,000-mile trip from Georgia in their opening game, Northern Ireland had to quickly reset and O’Neill admitted he saw “two tired teams” at the end of the game.
“I think our preparation, our first game in terms of being away from home and everything, was more difficult.
“I felt like Hungary got a little bit stronger towards the end.”