The west Londoners went into Saturday's match on the back of defeats to Aston Villa, Swansea and Manchester United, but did enough to overcome the resilient Canaries 2-1 at Craven Cottage.
"I think we played well in the first half and should have scored a few more goals to maybe kill the game off," the Norway international said.
"We knew they were going to keep pushing us in the second half and we tried to be compact and take our chances.
"But we didn't play well in the second half, we let them come back into the game and when they scored we just defended with everything we had.
"They could have nicked the draw but we are very happy because after three defeats in a row we need that win."
Riise and his team-mates may be buoyed by the victory, but serious questions remain over their concentration.
Aaron Wilbraham's goal for Norwich was the 17th goal the Cottagers have conceded in the final 15 minutes of league games this season - more than any other team.
"I don't know what it is, it just seems to happen to us," Riise added. "We know we normally play well at home and kill the games off, but if we don't do that they get a goal, they gain momentum and put pressure on us.
"Norwich scored and they got the momentum and we just couldn't keep the ball. That was the problem in the second half."
Source: PA
Source: PA