Class issues

Hi, I’ve just started using classes to program my flash game/apps and I’ve already began running into problems. I made a code similar to this in a flash game bfore, but cannot get it to work properly with my class I’m writing. What am i doing wrong?

[AS]
class Human extends MovieClip {
//Variables
//_Spawn Points
private var SpawnX:Number;
private var SpawnY:Number;
//_Movement
private var arrowTimer:Number;
private var arrowUp:Boolean;
private var Walking:Boolean;
private var Dashing:Boolean;
//End Vars
//////////////////////////
//Constructor
function Human() {
SpawnX = _x;
SpawnY = _y;
}
//onEnterFrame
private function onEnterFrame():Void {
//Arrow Timer
arrowTimer++;
if (Key.isDown(Key.LEFT)) {
if (arrowUp == false) {
if (arrowTimer<12) {
Walking = false;
Dashing = true;
} else {
Walking = true;
Dashing = false;
}
arrowUp = false;
arrowTimer = 0;
}
} else {
}
arrowUp = true;
Dashing = false;
Walking = false;
}
/////////////////////////////////////////////////////////////////
}

[/AS]