Blues were indebted to Hayden Mullins, who scored his second goal of the season on his return to the side after missing the last 19 games.
McDermott said: "I thought we should have got something out of the game. When it was 0-0 we were on top and then they scored from nothing.
"When I arrived at the club I put my reputation on the line and to make sure Leeds remained in this division. So far as I am concerned it is job done.
"Everyone must be going in the same direction. If that occurs in this club you have a major chance.
"I think we have to talk about who needs to come in. If we can add to the squad with good quality players who know this division we should progress.
"Leeds were possibly in trouble when I came in. I am delighted with the boys. They played two games at home and we won them both. They were pressure games."