He told reporters after the game: "We started well, we were comfortable first half and had chances. But conceding twice through set plays is disappointing.
"Crystal Palace make it difficult for you, but we lost control in possession and were second best second half.
"Palace made it difficult for us to break them down, but you have to take the chances you create and that's the difference."
The result leaves Pearson's side in 10th in the Premier League table.