Robin van Persie believes he could have done even better for Manchester United despite scoring 22 goals since joining from Arsenal in the summer, and says that since moving to the club he has felt like a "kid in a sweet shop".

The Dutchman scored again in Sunday's 1-1 draw at Tottenham Hotspur to continue an impressive start to his United career, following a £24m move. Yet Van Persie is ruing the fact that he has not scored more. "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," he said.

With the Holland striker having scored 10 in the 10 matches before the draw at Spurs, he was pressed about how successful he has been. "Not really well. It is going well but if you start to believe it's going well, you're going down," he said.

"When I look back at those last 10 games it's a good step but to me it should have been 10 games, 14 or 15 goals. At least four or five I shouldn't have missed."

United lead Manchester City by five points, and Van Persie is finding life at Old Trafford rewarding. "Arsenal is a great club and I always had a really good feeling, but after eight years sometimes you feel that you need a new challenge," he said. "I know why I went and I'm sure it's for good reasons.

"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. When I first came to Arsenal years ago [in 2004], I saw things from [Dennis] Bergkamp and Thierry Henry I'd never seen in my life 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: 'Yes, this is nice, 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."

Two of those are Ryan Giggs, 39, and Paul Scholes, 38, and Van Persie, who is 29, says their longevity is inspiring him to play for as long as he can. "To be fair I always thought that I would go until very late [in his career]. When I see these boys, against West Ham [in last week's 1-0 FA Cup third-round replay] Giggsy just ran the show. He was incredible."

Have the pair surprised him? "Yes, very much. I always thought they were great players but when you're with them every day in training it's great fun to be part of that. Giggsy – every single touch is the right one, every single move. He's so experienced," Van Persie added.

As for Sunday's draw at Spurs, who equalised in injury time, Rio Ferdinand told MUTV: "The way the game panned out was disappointing. We defended for our lives as a team and got a really good goal through Robin, so it's disappointing in that sense. But we've done that [scored late] to so many other teams in the past that sometimes you just have to take that on the chin.

"As soon as I got off the pitch and in the changing room I thought back to how many times we've done that to other teams and you've got to accept it every now and again, especially if you don't lose the game. It's a difficult place to come and you just have to dust yourselves down and say: 'OK, we'll take that point.'

"We're in a good position but nothing is won yet and no medals are given out now. You've just got to keep chalking off the games and picking up as many points as you can. You want to get the difficult games out of the way and this is one of them. I think a lot of teams will drop points here."