Manager Rafael Benitez felt Newcastle were victims of a "soft penalty" decision as fellow strugglers Crystal Palace came from behind to earn a draw.
Mohamed Diame had turned home Kenedy's corner at the back post midway through the first half for the visitors.
But Luka Milivojevic earned Palace a point with a second half penalty after Ciaran Clark was penalised for pulling Christian Benteke's shirt.
"He was pushing my player and my player was pulling," said Benitez.
"We cannot do it, but I can see a lot of penalties not given. We then changed everything because obviously they had more confidence and they were pushing, we knew that they have very good players up front. We needed to be strong in defence and it was difficult."
Former Newcastle striker and manager Alan Shearer also questioned the penalty decision on Twitter.
"If that's a penalty then there should be 10 penalties per game," he wrote.
But speaking on BBC Radio 5 live sports extra, former Premier League striker Steve Claridge felt the decision was much clearer.
"You can just see the shirt being pulled. Yes, it's a penalty. It's a definite pull on the shirt. Absolutely. A stupid, stupid thing for Clark to do."
The point lifted Palace up to 14th, with Newcastle remaining 16th but a point clear of 18th-placed Stoke.