Villa were worthy victors as a double from Morgan Rogers canceled out Matheus Cunha's goal for the visitors.
The win leaves Villa third on the Premier League table at Christmas, three points behind leaders Arsenal.
But Emery said of their title chances: "The realistic is the capacity and potential and we have played a lot of team like Arsenal and Manchester City. Of course we beat them here, but they have massive things tactically with players on a high level. And we have as well but to be a contender in front of them is our reality where is not.
"We are not contender. We are here because we are competing fantastic. The players are really focusing each match with what we are trying to set and being consistent. But we are not contender to be there.
"Of course we are being consistent in more or less three years, and getting into European positions, but we must continue to be humble. And understanding how we can get points like we did. We want to keep the same level by being intelligent, competitive, consistent and demanding. Through it we are here."
On Morgan Rogers and his team's second-half performance, Emery admitted: "He was not performing very well in the first half! He scored a good goal but he was not performing very well.
"We spoke about individually increasing our focus to get better and in the second half we did much better. At half-time I was not happy (with him) because I am ambitious myself. I share my ambitions with them and my demand.
"Of course the players were performing but we weren't focused enough. We weren't facing them, or getting duels like we planned and needed. The second half we were better. Today was a matter of playing forward because they wanted us to pass back so they could press us and create difficulties."