"I'm not going to be too critical of the lads because I thought we played well," Johnson said after the 1-1 draw.
"One good header from a set piece would have cleared it and won us the game.
"We conceded some unnecessary free kicks and if you do that and invite the opposition to put balls into the box you are asking for trouble.
"It won't be easy looking at the video of the equaliser and I couldn't face the players with a smile after the game.
"I was pleased with a lot of our play and I hope our supporters won't forget how well we passed the ball.
"It was good for Alvaro's confidence that he got a goal and I am sure that he and Nicky Maynard can form a successful partnership."