Are you using rigidbody physics for the character movement? I recommend either a faster acceleration with high drag, or swapping to a character controller for snappier movement. Basically, the movement should not be something that draws the player's attention away from the rest of the gameplay, because it seems like you want to experiment with exploration and risk/reward. If the player becomes frustrated with the movement, they are unlikely to enthusiastically engage with the rest of the game. That's just tuning though, so it shouldn't be too hard to play around with and come up with an improvement.

Walking mechanics are a bit tiresome, but the next day messages are very funny hhahaha

I like the graphics - and like the idea of how the gameplays.  Would have been nice to have a gui to have some indication of how much you have mined.  Great game to use as a starting point to keep going.

I think the animations need some work, the pickaxe animation, for example, doesn't sync up with the bar dropping nor with the sound effect playing. And the walking animation feels like it needs to be synced up with the actual walking speed a little more. But minor animation issues aside, I think this game was really well done. The backgrounds are beautiful, the music sets the perfect tone. From a gameplay standpoint I really like the idea of seeing how far into the mine you can go and still get back, but I think it takes a little too long to actually get back, and you're left simply holding down the button for a very long time. I'm not sure what sort of fix could work here, but thought I'd voice the thought anyhow. All said, it's a great game and very well suited to this jam!