The AFC East side were beaten 34-31 by the Atlanta Falcons at the weekend, which was their fourth loss by three points or fewer in 2013.
The head coach told reporters: "It's extremely disappointing. You have opportunities and we had many opportunities during the course of that game to get ourselves a win, we didn't capitalise on those opportunities. At the end of the day, you lose the game and it's tough to deal with.
"For us we've got to come back and come back strong. I told the team that we haven't won a quarter yet, how we break down the season. That's our goal, to go out and win a quarter. We have a tough slate ahead, three out of four games on the road.
"We've got to learn to win those games and we've got to learn to win close games. We have to learn how to win games on the road, we have to finish teams and that's the thing that's tough. Obviously it's my job to win football games, and I'm going to do everything I can."
The Bills face the Tampa Bay Buccaneers this weekend.