Crysencio Summerville struck before Richard Kone's goal for QPR took the tie to extra-time. Taty Castellanos hit the winner on 98 minutes for the Irons.
Nuno said afterwards: "It feels good for the fans, (it feels) special for the fans who have been supporting and not (getting the results) back.
"Today we go home happy as I think we played a good game and we deserved to win.
"We were organised, I think it was a big fight, but in terms of the game, the way we played was good. We were in control, we were dominant in the beginning of the second half and we created so many situations that we need to try and click for the final pass, the final assist.
"Overall the spirit, the fight, the desire, the character of the boys, especially in this situation, it makes everything better for us. Hopefully the week is going to be better.
"Cry delivered today, Jarrod also, (they played) an amazing game.
"Taty, Pablo… I think for the front players goals gives confidence and hopefully for all of our attackers we can have a boost of confidence that we're going to need.
"They bring us more options. We are trying to rebalance the squad, we still need bodies, but today was a very important day for us."