Since his summer move to Old Trafford, the Netherlands international is the Premier League's leading scorer with 18 goals in 23 appearances.
The 29-year-old has netted in all but one of the 11 games he has featured in since Nov. 28 but is adamant his record could have been better in front of goal.
"It should have been 10 games, 14 or 15 goals. At least four or five I shouldn't have missed," Van Persie told reporters. "It's not going really well. It is going well but if you start to believe it's going well, you're going down. "If I look at all those games, I should have done better in most of them because I had more chances than just one chance and one goal."
Van Persie admits he left Arsenal to be with players who have experience in challenging for the Premier League title and claims he is now "like a kid in a sweet shop" with the wealth of talent he has around him at Old Trafford.
"Arsenal is a great club but after eight years sometimes you feel that you need a new challenge. If you look at the last couple of months it explains it all. I'm seeing things again that I didn't see for a long time," he added. "For the moment we're in a great position. We are ahead on points, goal difference is in our favor. All these guys here know how to win and become champions.
"When I first came to Arsenal years ago, I saw things from Dennis Bergkamp and Thierry Henry I'd never seen before. Now I'm seeing those things again and that makes me really happy. It's like a kid in a sweet shop. It's like, 'this is good, this is having fun, this is enjoying yourself'. All these little things added together make a big difference. It makes me feel that I'm surrounded by champions."