Rafa Benitez's men enjoyed a strong start to the campaign despite failing to land a number of their transfer targets over the summer.
Four wins in seven matches between the end of August and October moved them into the top half of the table.
However, the Magpies have now started to struggle and Benitez's men have lost five of their last six games.
Leicester and Everton are up next for Newcastle and Perez has warned his team-mates that they cannot afford to not win.
He told reporters: "We have to get a win now. We started the season pretty well, and that’s helped us with our league position, but we have gone too long without winning a game, and we have to put that right.
"We are at home for our next match, and we have to make the most of that and get three points. We can’t keep saying we’re still OK in the table. This is the moment to start turning things around and get back to having the winning feeling again."