City are now 11 points runaway Premier League leaders Liverpool.
“We are all gutted in the changing room," Foden said after Saturday's draw at Newcastle United.
"We wanted to get the three points today and it's disappointing after their goal. We need to move forward and focus on our next games.
“We thought that [De Bruyne's goal] was going to be the winner. But they kept going and they manage to score a great strike in the end, unfortunately for us.
“It's not in our hands now [the top of the table]. All we can do is win every game, it's going to be a big challenge for us.
“I think [December] is the most important time of the season. Teams usually drop points, it's going to be interestng. All we can do now is to try to win all our games and see where it takes us."