Very hard to tell what can kill you and what is just part of the background. Movement is rough and i think some sound effects should be added when you are hurt. Also a life bar so you can take multiple hits would be nice. :-)
From what i can tell it's one of your first games and also it was made in a game jam so time constraints were a factor as well. Considering that i think this is well done. Good game!
Looking forward to your future projects.