City have steadily come up on the rails this campaign, spending much of the season outside the top six having played fewer games than most of the teams at the top.
But victory over Crystal Palace eased City above Leicester and Liverpool into second – just two points behind leaders Manchester United but having played a game less.
The boss says he is proud of how his players have fought to climb the table.
“We fought a lot to be up there like many clubs and we will have to fight a lot to stay there,” said Pep.
“It is a weird season. Everyone can beat everyone and it is difficult every game. I am happy for the players. It was a good performance, another win and three points.”
Asked if it was the perfect 50th birthday present ahead of tomorrow, he added: “Yeah, thank you so much for the players!”
The City boss also praised the contribution of John Stones who scored twice in the 4-0 win over Crystal Palace.
“If there's one guy who deserves the best it is John,” he said.
“He is a fantastic human being; his parents must be so proud of him. He has had problems in the past. A manager can’t give a player confidence. He has started to play and alongside Ruben they play really well.
“But everyone, you saw today, the way we pressed, how aggressive we are. How intense we are. It is so important. It is so good. We cannot deny.
“The guys behind do not make a mistake. They are so consistent. Last season it happened many times that the opponents didn't do anything and we gave goals away.
“This season we have improved a lot. We concede few and the quality of players up front make a difference.
“The managers can help many, many things, but the one thing we can't is the talent up front.
“We are incredibly fortunate and lucky to be in charge with these kinds of players who make your life easier.
“In this kind of game the past two seasons we have struggled to beat them. Today I understand why. It is the quality of the players up front.
“This is a special thing, but the managers are not involved.”
And on the excellent for of Ilkay Gundogan – who bagged his fourth goal in six games – he said: “Ilkay said perfectly the year when we won the second Premier League and won 14 games in a row (was perhaps his best form).
“He played as a holding midfielder and was incredible. I have a feeling the league win wouldn't have been possible without his quality and vision there.
“He is a player who when he plays close to the goal he makes the moments to score a goal. It is not easy to find a defensive midfielder who can play as a number 10 as well.
“it was a fantastic goal and it helped us in the second half because 1-0 is always open.”