The Hammers were beaten 4-1 at White Hart Lane, and the heavy defeat was not something which Bilic’s men have become accustomed to this season.
West Ham have been excellent on their travels this season, but they came unstuck against an impressive Spurs side.
And Bilic said: “I cannot pretend I am not disappointed because I am and the dressing room is very, very quiet, of course.
“We are all disappointed and it simply wasn’t us. We didn’t play good.”
Tottenham were 4-0 up against West Ham, before Bilic’s men did strike a consolation through Manuel Lanzini late on.
The Lilywhites took the lead through Harry Kane, and they never relented, with Toby Alderweireld extending their lead, before Kane added a third and Kyle Walker completed the triumph.
The victory lifts Tottenham closer to the top-four, while West Ham’s hopes of breaking into the Champions League qualification spots have been dented.
The Hammers are now five points behind the top-four, but they are still in sixth place in the Premier League table – having made an encouraging start.