Good job on finishing a game for a jam.
Some honest feedback about it.
First of all, the controls are bad. It's hard to understand where forward, especially when the camera rotates. This makes the the gameplay experience really bad.
The theme fit doesn't really come out in the game. Yeah it's drowning, but this drowning mechanic could be replaced or taken away and the game wouldn't change. Also, the problem with the mechanic is that having a time limit means that the levels are designed around that time limit. Meaning that it's not really a challenge because you have to make sure the player can finish the levels. This could be fixed with a longer time limit and adding challenges into the levels. This way the player has a time limit on getting past these challenges.