I don't want to be unkind, you guys had put a lot of heart and effort in this game thats sure. But I think constructive criticism is one of the key to get better.
That being said, I agree with one of the comments down below, I will say the game is too unfair and frustrating. The level design is too unforgivable and the difficulty curve really too steep. Mix that with the slow pacing and you get, in my opinion, a mostly non-fun experience.
I would recommend you to split your level into many mini ones (like mini golf?) , with unique idea/mechanic for each one and a progressive difficulty, to give to the player a sense of achievement, short term objectives and a long term goal aswell, that's what good games are made of. Also speed up the shot charging and/or completely rework this mechanic, its too slow and redundant.
You guys should go check a game called "What the golf" if you don't know it, to inspire yourself , I think it is a great example of a "boring" game becoming fun thanks to good game design and level design. I know 3 days is short to make a game, I know how its hard. I hope I haven't been too harsh with you...
PS: you can skip 95% of the level by passing over the wall then landing on the other side, on the 2nd slope.