I think you just got a harder one at that time. The fastest time I ever had, was 1 hour! and I even reset many-many time before I could finish that.

But the one problem that I encountered was that even though I finished it more than 1 hour, it seems that I didn't get any coins. Even though the games said that I get 100 PixCoin for finishing the game > 20 mins. But until now, I still don't get the 100 PixCoin reward yet.