The Netherlands international joined Newcastle on loan from Borussia Monchengladbach last week after enduring a frustrating first half of the season in the Bundesliga.
The striker appeared as a half-time substitute in the Magpies' 3-0 derby defeat by Sunderland on Saturday and was frustrated to not score.
However, De Jong is confident he can get among the goals once he is up to full fitness and has targeted a long-term deal at St James' Park.
"I'm really happy to be here playing for such a great club," De Jong, who was Newcastle's only January signing, told the Shields Gazette.
"Hopefully, I'll play for the club for a long time, and in the summer I can stay. That's my goal, of course. We'll see what happens.
"I'm happy to play again. Hopefully, we'll go on, and my goals will come. I'll have to keep on working.
"As a striker, it's disappointing when you don't score. When I get more matches, and get a good feeling, I'm sure my goals will come."
De Jong also acknowledged the players' disappointment and frustration after Newcastle were beaten 3-0 at home by Sunderland for the second season in a row.
He added: "Everybody told me how big it was. The atmosphere before the game was so huge, and that makes it even more disappointing to lose the game. It's just so frustrating.
"Before the game we talked to each other about how important this is. It was disappointing and frustrating. It was such a big game. We wanted to win it badly."