Hi, thank you for playing our game and for your review!
To quickly clarify, the mouse has three stats: health, speed, and lifespan. The health is how much damage you can take from enemies and the lifespan is how many seconds you can survive in the maze for (represented by the timer on the screen). If either the mouse's health or its lifespan reach zero, the mouse will die. This is why the mouse died even though you avoided the enemies.
(If you were dying before the lifespan or health reached zero, please let us know, since that is a bug.)