I think the premise is there. In terms of level select, I think 5 seconds is pretty slow, but I did like how you communicated that to the player. The average game would have no flashing numbers and people would get confused. I got stuck on level 2, I wasn't able to hit the right side of the block. Regardless of that however, I think your gameplay is decent. Your jump sometimes feels off (side note, do you use a raycast for ground detection?) but for 48 hours this is pretty good.