I don't really understand how to play sardine smash very well... can some1 plz help me? my sardine keeps having this dead looking face on him, and it won't let me hit with him again. I really don't understand this.

You have to be a bit strategic with your hits. You can't go crazy with it otherwise it would be too easy. Your fish gradually gets more and more red as a sign that it's getting closer to "dying." So space your hits out a bit and see if that works.

And if your computer is running a bit slowly, it can mess up how quickly your fish revives. If you're having difficulty and it becomes literally impossible to pass a level, I suggest muting the game, then right clicking, scrolling over "quality" and setting it to low. :)