Solid concept!
The art overall works together, so good work on aesthetic!
You mentioned you would like constructive feedback, I'll do my best.
As I see you have a lot of feedback already, I would like to give the feedback that you have different resolution art together.
So your character is high res (looks good!), but then you have a lot of elements/objects that are pixel art (also good). That causes a mismatch visually (bad together).
I'd recommend to stick to one end, so just pixel art or just high res to keep art cohesive.
For your first game/jam, this is great!
You made a unique idea into life and I hope you will always be proud of this milestone, keep it up!