The Gunners never really got going against a side which had leaked goals in recent weeks but stepped up their performance to record a first Barclays Premier League win under Chris Hughton. Wenger knows Arsenal need to produce a much-improved display when they take on Schalke aiming to secure a place in the last 16 of the Champions League.
"I hope it will have a positive impact," Wenger said. "It was a shock to the system, but you have to give credit to Norwich because they played well, were completely committed and they deserved the win."
German forward Lukas Podolski flashed an early drive across the face of goal, but it was Norwich who struck first when Grant Holt netted on 20 minutes after stand-in goalkeeper Vito Mannone had palmed Alex Tettey's shot back into the six-yard box.
Arsenal enjoyed plenty of possession as Norwich defended deep, but could not carve out any meaningful openings.
Olivier Giroud - who had scored his first Premier League goal at West Ham before the international break - hooked wide after John Ruddy's punch, while Mikel Arteta's late low drive was the only real save the Norwich goalkeeper had to make.
Wenger added: "Maybe we underrated the difficulty we would face, but the Premier League is the Premier League - if you are not ready for the fight then you will always have bad surprises.
"There is a big difference between the amount of possession we had and the amount of chances we created, that is down to the fact that Norwich defended well and we did not create a lot."
As with every international break, nearly all of Wenger's first-team squad were away, while Norwich still had the majority of the group to work with. Wenger, though, was not about to hold it up as an excuse.
"We have to deal with that," he said. "You could say we have better players but there is only one way to show that, on the football pitch."
Source: PA
Source: PA