The visitors scored two quick goals in the first 70 seconds as the game kicked off to send a half-empty terraces into panic.
Ozil has been ruled out of Thursday's Europa League game against Ostersunds after he spent Monday and Tuesday in bed, Wenger said - although he may have been rested anyway given Arsenal's 3-0 lead from the first leg.
"We were nowhere near it, especially in the first half", the England worldwide told BT Sport.
There were tragic scenes in Bilbao, though, where a police officer died following clashes between fans ahead of the meeting between Athletic Bilbao and Spartak Moscow.
However, he would not comment on reports that the officer died as a result of the violence.
Despite suffering a 2-1 defeat at home, Arsenal triumphed 4-2 on aggregate to secure a place in the last 16 of the tournament, with the draw for the next round taking place on Friday.
Ostersunds sensed the hosts' complacency and Hosam Aiesh stunned the Emirates 22 minutes in, latching onto Saman Ghoddos' long ball in behind Kolasinac and firing across David Ospina, with Chambers deflecting the effort into the net.
Having been knocked out of the FA Cup early on, they had a weekend off this weekend so they should be fresh, although they will have one eye on the League Cup final against Manchester City this weekend. Overall we responded very well. We have to get through tomorrow and then see who we get if we get through.
The Armenia midfielder provided three assists on his debut in the 5-1 Premier League win against Everton, before creating two of the goals in the 3-0 win against Ostersunds last week. "But ideally, we want to come back to the Champions League through the Premier League".