Interesting! The game looks and sounds great. I also found it to be fairly difficult.
I finally reached the end of the level and got to race my doppleganger - then I was really sad that the doppleganger went away again after I fell in a pit. It was like being kicked back to the first level after I'd reached the second. I went ahead and played until I saw the doppleganger a second time, but after losing again I don't feel compelled to keep playing the same challenge over and over. I feel like my personal problem is less that the game is too hard, and more that it's too punishing.
It seems like there are some natural checkpoints in the level (the tunnel sections) and I wonder if they could be used to introduce the doppleganger earlier, or not send you back as far when you fail. I also want to know more - why is there a copy of me? Can I interact with it? Why do I want to beat it to the end of the level?