Mourinho accused the North Londoners of failing to make good use of their chances as Liverpool leapfrogged them to claim top spot in the Premier League.
Mohamed Salah put Liverpool ahead inside 26 minutes, but the visitors hit back seven minutes later thanks to the in-form Heung-Min Son.
Spurs missed a host of chances inside the second half to secure a rare Anfield victory. The game was heading for a stalemate before Brazil striker Roberto Firmino headed the winner to give Liverpool the three maximum points.
"I think even a draw would have left us not with the best taste because we had them there to win it," Mourinho told his post-match press conference.
"It was not just about the big chances, it was the moment of the big chances. The moment was when they were in trouble, in their worst moment, and we had it there to kill it and we missed it.
"Normally, in matches of this level, you pay [for] it. I thought we were going to pay [for] it by just taking a point, but in the end, we did not even take a point so it is very disappointing."
“The draw will probably be a fair result but to lose it is really, really unfair. But that's football.
"In the end the destiny decided for them to win it. Also in a very strange way for me."
Tottenham will go again on Sunday in a home Premier League game against Leicester City.
