It was a first defeat in five games for the Blues.
"We needed to use the momentum from getting the first goal at home," said Chalobah to chelseafc.com.
"It was the great start we wanted and we tried to attack more.
"We knew exactly what we were going to face, a team full of togetherness. They showed that. They tried to disrupt our game. In the first half we had chances, in the second half we were creating but one switch-off at the end and that’s what it takes.
"It’s very disappointing. It’s a game we needed to win, at home as well. We’ve been very good playing at Stamford Bridge, and the recent form we’ve had, so it’s a disappointing one.
"It was not our best game as a team, but these are the games we have to learn from and take it into the next one."
The England defender added: "We need to improve when teams come and disrupt us and sit back, and we need to break them down. You are going to have moments like this in a season. Any team you play in the Premier League is going to be a battle.
"We need to work on consistency, we had those three defeats (to Bayern, Man United and Brighton) but then we won four games in a row. So we need to keep working every day, learn from it and move on."