Thanks for giving it a play.
I added some extra help in a post-jam update (that I haven't uploaded yet) which should address the issue of not knowing how to close the help screen/drink a potion etc.
You're not picking up a new knife every time, just swapping back and forth with your starting knife (there are other weapons too). :D
I was quite interested to see how you approached the sun system, I guess that could be better explained somehow as it seems you didn't quite get it.