The Magpies made a dream start as they were gifted the lead with only four minutes on the clock as James Perch struck, but United were back on level terms soon after through Jonny Evans.
The moment of controversy then arrived as Danny Simpson's low shot from the right corner of box was turned home by a sliding Evans. Assistant referee Jake Collin's flag went up for offside against Papiss Cisse, but referee Mike Dean eventually gave the goal as he correctly ruled the Newcastle striker had not touched the ball.
After protestations from United boss Sir Alex Ferguson, and a further flurry of goals in the second half with Javier Hernandez netting an injury-time winner, Pardew said he couldn't see a problem.
"At the time I thought it was an own goal," Pardew said. "It doesn't matter who is offside, he could be 20 yards offside if the defender sticks it in.
"I don't know if the striker got a touch before the defender but I don't think so. I can't see a problem with it."
There was further controversy in stoppage time when Antonio Valencia slid in on Vurnon Anita, leaving the Newcastle man to be stretchered off with an ankle injury.
"I was a bit upset with that tackle," said Pardew. "I have seen it again and I don't think it was malicious but Valencia has mistimed it badly and unfortunately it might cost us a player.
"I am not sure what is wrong. It is too early to say. It is a bang on the ankle. We will have to see whether he will make Arsenal, which would be a loss to us."
Pardew also confirmed midfielder Jonas Gutierrez faces a spell on the sidelines with a knee injury after missing the Boxing Day game.
"He will be missing the next two or three games," he said. "Gutierrez will have an injection in his knee tomorrow. It is not clearing up and he is not 100%."