The England U21 captain scored deep into stoppage time to rescue a point for the Gunners.
Opportunities have been few and far between for Nketiah this season, but the 21-year-old was happy to capitalise against the Cottagers.
"It's great to get on the scoresheet and salvage a point for the team," Nketiah told the club's website after the game.
"We fought very hard and we were very good at the tail end of the game, so I think it's the least we deserved. It's always nice to score for Arsenal.
"It feels good, to be fair. It's a bit of belief, I think it's the least we deserved, like I said. Of course we would've wanted the three points, but in the circumstances and how late it was, it has to be good to at least get a point."
He added: "I think I had a very good first half of the season, I was getting a lot of games, but in recent weeks I've not played as much as I would've liked to.
"It's been disappointing but I always work hard, prepare well and make sure I'm ready when I'm called on. It's always nice when you get the chance to make sure you take it, like today, and luckily I did."