The midfielder has missed only three of City’s 39 games in all competitions and says he was feeling tired during Saturday’s 1-1 draw at Burnley.
“I was feeling it from the first minute,” he said. “I’ve said it before — you feel great for 10 games, then you feel OK for 10 games, and then the rest you feel like shit.
“You know, we’ve got to do what we’ve got to do. We’ve only got 15 or 16 players available at the moment so we need to get through it.”
Injuries to Benjamin Mendy, Gabriel Jesus, Leroy Sane, John Stones, David Silva, Fabian Delph, Phil Foden and Lukas Nmecha restricted City boss Guardiola to just six substitutes at Turf Moor.
The runaway Premier League leaders are not in action again until Leicester City visit the Etihad Stadium on Saturday — their longest gap between games since the November international break — and Guardiola has decided to give his entire squad three days off.
“It will do us a lot of good,” said De Bruyne. “I’m going away, it doesn’t matter where.”
City should have claimed all three points at the weekend after dominating the match.
Danilo gave them a first-half lead but they were unable to add to it, with Raheem Sterling spurning a gilt-edged chance from close range before Johann Berg Gudmundsson claimed a late equaliser.
“Nobody is complaining about the way we played,” said De Bruyne. “I think we played really well and we should have scored more but it happens and it’s not even bad defending, it’s just the way it goes sometimes.
“Obviously it’s very hard and we haven’t got any players left, so maybe we feel a little bit of tiredness which makes it a little bit more difficult but I thought the way we played was exceptional.”