Well done! It is very difficult to submit your first game Jam.
A few suggestions:
- A block placing game can really use a grid along which the blocks are place.
- It is currently possible to place blocks on the character, which can be used to clip through the ground.
- It isn't difficult to add sound effects in unity, and those can be found for free online.
And there were some small things, such as the horizontal dynamite was partially off screen for me. Those issues usually arise when you play the game in a different screen resolution then usual.