I'm not sure wether audio was supposed to be there or not, but I didn't hear anything. Overall the concept is cool but I think it would benefit if it was more fast pace, that way it's easier to make mistakes and go onto the next game. I am thinking kinda Wario Ware ish here, where most minigames only take a really short amount of time. And well audio I think would also make this more intense and more hype. But overall a very good start to a game.
Now a little bit more nit picking about tetris. While I don't know exactly how it works myself, the order of tetris pieces is not entirely random. I am pretty sure you get something close to the 7 pieces but in a shuffled order, at least the start. also my T piece got rotated and turned into an S piece xD However this wouldn't be something I would worry about I just wanted to point it out
In snake my dot also never moved after collecting it
Good luck on your next projects and keep at it!