Hrm...
Being an author, I know what its like to get bad reviews on a game that was probably difficult to make.
However, I would need to comment, although theres no rule saying it needs to be in english, you really should post in english.
If you wanna use japanese, you need to know that no matter how good it is, 90% of reviews will comment on this and drop your scores.
Because there was very little text in it, you can get away with it, but its not easy. What I would do if I were you, is, because it looks like your fluent in english, is maby changing the language.
In Universe 3 (an unrelated game I'm working on) I was debaiting about language, and decided to use dynamic text for displaying translatoin text. That way, in the loading screen, if you were to click on the language of your choice, you could more easily play. you might want to do that.
Next up, is the system. Maby you could add instructions, and a few more levels. As for how much fun it is, it needs somthing to add stress. a 100 second countdown isnt very stressing. maby have the duck move through slowly... have it so the person streses out with the tilgea on his tail.
-Raraken