Looks neat! I've never worked in GameMaker before, but how do you increase and decrease the speed? It seems like you may be changing the frame rate? It stutters a lot on certain speeds, not really sure what's going on there. Also, I found a reproducible bug where you can't restart if you jump, press R while you're in the air and then land on your head. And to quit the game I have to press alt + f4.
But yeah, the game does look cool and I think you could make this into something cool. What if you can also vary the turning speed by for example holding the jump button? Good luck next game jam! :)