Emery insists Villa dominated the match, but Palace's finishing was a level above.
"I’m sad for the supporters and sad for the result after we were being successful here at home for a long time without losing,” Emery said.
“We played the first half good, but we needed more offensively. We had one very good chance with Ollie Watkins and we didn’t concede a lot, but we made one mistake and they scored.
“In the second half, we were trying to speak about how we played the first half and how we were keeping the same game plan and trying to do something more, and we started very well.
“We were dominating, getting in their box and creating some chances, but the second goal was the difficult moment and the third goal was punishing.
“We have to accept this defeat and try to keep balance. Overall, we are being successful, but we can feel more frustrated when we are losing like today.
“Now we’re going into a break and we’re going to have a lot of players with their national teams.
“This is our development and a consequence of how we are increasing our level and getting a better level as a team with the performance of the players, a lot of players in their national team.
“When they’re coming back, we’re going to work. We’re trying to build a team.
“I’m confident we’re going to come back from the moment we’re in now.”