The hosts led the Premier League clash at St James' Park thanks to first-half efforts from Loic Remy and Yoan Gouffran, but the pace of the game dropped off after the break and Leroy Fer was able to net a consolation strike for Chris Hughton's men.
And manager Pardew believes his players' international duties over the past fortnight contributed to their apparent fatigue in the second period.
"We looked a little bit tired second half with some of our players who travelled around," he said. "When you're 2-0 up at half-time, you kind of start sort of leaning on that a little bit.
"Norwich did well second half - I don't want to take anything away from Norwich.
"I thought they applied themselves well and I though Fer announced himself on a big stage here. He was terrific for them.
"I felt we were very good without the ball today - very disciplined, very organised. It was with the ball that we wasn't at our best."
But the 52-year-old said his charges did enough to deserve the victory.
"I still think we did enough for the win," he continued.
"I think we should have got a third goal before they scored. We wasted some good opportunities.
"Up until they scored I felt we were in total control, I think Norwich fans cheered when they got a corner.
"They didn't look like they were going to penetrate us, but then we had to defend very well that last 10 minutes to make sure they didn't get anything out the game.
"I'm as pleased (with the result) as I was when we won at Spurs."
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