Hello!
Great work! I really liked your asset selection. The music was nice and the graphics were appealing.
I enjoyed playing your game and I think I discovered everything.
Here's some feedback that might help you improve your game later. But take it with a grain of salt, because I have my own opinion, which may differ from your design philosophy.
Speaking of opinions, I'm really not a fan of using the arrow keys to move. I'm just used to W/A/S/D, which feels much more natural to me.
It also means I'm not as comfortable moving around with it. This ties directly into my next point. I would lower the gravity and make the character float a bit more.
Not a lot, but just a bit, so he'd be easier to control. I would also increase the jump height to make tight jumps a little easier.
I also noticed that you are using a capsule collider. I prefer box colliders so you don't slide over edges when you barely do a jump.
Also: Have you ever heard of "Coyote Time?" It's a very useful tool that makes jump'n'runs feel much more responsive and forgiving.
I liked that you can jump on enemies (at least the slimes) to defeat them. I actually preferred this method, as melee attacking "stunned" me for too long.
A single weapon swing instead of two would reduce the commitment needed to start a fight, and the fight would feel much more dynamic. Maybe give the player a little bit of forward movement to make it feel more dynamic.
I would also add a knockback effect to the enemies.
Anyways, keep up the good work and you will be improving very soon :)