Wilfried Bony's stoppage-time penalty on Saturday heaped more misery on the north-east club and Pardew could only watch on from the stands at St James' Park as the Welsh side snatched a precious 2-1 win to ease their relegation fears.
Shola Ameobi's first top-flight goal since December 2012 had put Newcastle in front, but Bony equalised with a powerful header just before half-time and then sent Tim Krul the wrong way from the spot after Cheick Tiote had brought down Marvin Emnes.
Newcastle have lost six of the seven games that Pardew has been banned from the touchline for following a headbutt on Hull City's David Meyler, but he believes the latest setback was harsh on his out-of-sorts side.
He said: "That was a really cruel blow for the club and the team.
"It was a game that looked like it was going to head for a draw and we just switched off at our own set-play.
"It's cost us at least a point and in the position we were in the game, we didn't deserve that. I'm absolutely choked for the players and the staff, because even a point would have been something to carry forward."
Newcastle lost strike duo Papiss Cisse and Luuk de Jong to knee and hamstring injuries respectively in the first half and Pardew believes it played a part in Saturday's defeat.
He said: "We had a few blows in the game in terms of the injuries to Papiss and Luuk, our game-plan had to change a couple of times.
"We lacked a little bit of energy towards the end and probably those two substitutions cost us."
Loic Remy and Mathieu Debuchy returned from injury to replace Cisse and De Jong, but former Southampton boss Pardew will now await news of how long his latest casualties will be sidelined.
He added: "De Jong went over on his ankle and that doesn't look as bad as Papiss, who looks like he's damaged his knee but we'll have to wait and see for the scans."
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