Closest rivals Sheffield United suffered a heavy away defeat at Stevenage and Flynn said every point gained from now on was welcome.
"We can't rely on other teams," Flynn said. "We have to do it ourselves and make sure we stay on top until the end of the season.
"We didn't play as well as we can do - particularly in our passing going forward.
"The service to the front two wasn't good and our decision-making at times was not what it has been.
"When you are only a goal in front the other team is still in the game and you can't afford to give them any encouragement.
"But there will be ups and downs before the season is finished and the challenge is to stay positive."
Flynn refused to blame his side's performance on the bumpy pitch, but added: "Our away form has been scintillating.
"If we had matched it at home we would have been promoted already."