The Robins conceded a last-gasp goal against Peterborough at the weekend but Johnson is keen to point that, despite the negativity, the side are ninth in the table and just a point off the top six.
"It's important we don't allow ourselves to feel too down about what has happened because a win in our next game could put us back in the play-off positions," he told the Evening Post.
"We have to remember there are plenty of other teams worse off and with bigger problems than we have.
"The players and supporters need to dust themselves down, stay strong and try to put things right on Tuesday. We are still in a good position."