The East Midlands outfit went into the game at Craven Cottage looking to strengthen their hold of third position in the Premier League table.
However, Nuno witnessed his side go down to goals from Emile Smith Rowe and Calvin Bassey, Chris Wood having initially netted an equaliser.
With Manchester City overcoming Newcastle United, Forest now hold just a three-point advantage over the fourth-placed defending champions.
What did Nuno have to say?
For the 7-0 victory over Brighton & Hove Albion earlier in the month, Nuno had switched to a back three, a move that paid off as they ruthlessly dispatched the Seagulls.
Instead, his Forest players delivered an inconsistent and largely ineffective performance in West London, the Portuguese hinting after the match that he may have done things differently given the chance.
Nuno said, as quoted by the Nottingham Post: "We have to look at the game. We have to know that the change gave us more width and more things we are used to.
"But at the same time, the contacts in the box from the crosses were not there. We were rushing a little bit.
"There are so many things I would do differently now. Now it is about looking at the game and preparing for the next one.
"The idea of the formation was to have an extra body and try to control things better. What we anticipated, and what was the reality, was that Fulham's strength is having good players in wide areas. And then they occupy the box well.
"The idea of having an extra body to control that situation didn't happen. Unfortunately it didn't work out."
What next for Forest?
Forest now have an eight-day wait before their next fixture, a Premier League showdown with a Newcastle side that sit in seventh position albeit facing just a six-point deficit.
There is then the prospect of three successive City Ground fixtures, two of which come against Arsenal and Manchester City in the Premier League.
A home tie with Ipswich Town is scheduled between that double-header, Nuno highly likely to rotate his squad for that contest on March 3.
Written by
Darren Plant