A late Gareth Bale double secured all three points for the home side at the Cardiff City stadium, despite the Scots leading for much of the game after James Morrison struck on 26 minutes.
But with the pressure beginning to mount on the Scotland boss, Berra has admitted that the players are the ones who need to take responsibility for the result.
"It's got nothing to do with the manager - we are the ones who go out on the pitch," he told reporters.
"We played well, we just maybe ran out of steam a bit. A penalty and a 25-yard strike lost us the game.
|125/1||Scotland are 125/1 with William Hill to beat Belgium 3-0 on Tuesday night|
"At top-level football, it's the flip of a coin sometimes. We didn't have the luck."
With the Scots now second-bottom of Group A, their chances of qualifying for Brazil 2014 look increasingly slim.
However, the 27-year-old still believes his side are up to the task, despite requiring a shock result against Belgium on Tuesday to give themselves any real hope of making the finals.
He continued: "We're second-bottom. It's not a great position to be in.
"But we will look over the game and we will go to Belgium on Monday and prepare for the game on Tuesday.
"They are a top team, with world-class players, but we have done it before. We did in France [in 2007].
"When we're down, we always seem to bounce back."