Jean-Philippe Mateta struck twice as Palace won 2-0 on Saturday.
Nketiah told Premier League Productions: “It was a really good win. It’s a tough place to come but the boys put in a really good performance. It’s always nice to win, 2-0 as well.
“We played really well in the first-half I would say, it was just about that line, that final bit of quality in the final third – making that last pass, making that last movement and finish.
“JP got us off to a good start (early in the second-half), so I think the team grew in confidence, and all the boys that came on did well and made a good impact.
“I think we’re reaping the rewards for all the hard work we’ve put in all throughout the season.
“We’re not happy with where we are. We want to keep pushing and climbing up the table, and it takes performances like today, and results like today, to do so.”
On coming off the bench, Nketiah said: “As soon as I came on, I tried to go round the keeper and he made the save, but coming on for 10 minutes, I just tried to do my best for the team. Hopefully if I get more minutes, I’m sure the goals will come.
“(After winning the penalty) my natural instinct (as a striker) is to grab the ball, but we’ve got a set penalty taker: JP is the penalty taker.
“It’s not important about who scores – it’s about getting the three points, and I was happy to contribute.”