The Swans suffered their third defeat in succession after going down to a 2-1 loss at home to Tottenham at the weekend.
Michael Laudrup's Capital One Cup winners also lost against Arsenal and West Brom since hitting the 40-point mark in the Premier League.
But despite the South Wales club sitting in ninth position with seven games remaining, Williams has demanded some urgency heading into their clash at Norwich.
"We've got to stick together as a squad - we've all been in these situations before," said the Wales skipper.
"It's disappointing. We're as disappointed as anyone involved with the club and we've got to lift ourselves.
"We'll get our work done before Norwich. It's a tough place to go but we've got to get a win there really."
And he added: "We know it's only hard work, concentration and staying focused that will get us out of it."