Goals from Anthony Robinson and Danny Ings saw the Magpies slip to a club-record ninth consecutive defeat, and leaves Allen without a win after two games in his new role.
"You can't guarantee anything in football," he said. "The only thing I've said I'll guarantee is that the players give everything they've got, and that's what they are doing.
"There's no hiders and there's no shirkers."
He added: "Before I came I was told about Dagenham and Rochdale and us conceding in the first 20 minutes. I was determined that wasn't going to happen to this bunch.
"It is improving and we need that sooner rather than later."
Source: PA
Source: PA