shooting bullet in a platform game

I'm trying to make a platform game where the player can shoot a ball.

Weirdly my code seems to shoot the bullet, but I can't figure out why it's not shooting from my player.

It seems that, when the hero is above y= 160, the bullet is well aligned with the player. when the hero y below y = 160, the bullet is not aligned.

It's been hours and I still don't understand what is the problem.

Here's the problem :

Here's my code :

In my Main.as

public class Main extends MovieClip {
private var bulletList:Array = new Array();

public function keyDownFunction(event:KeyboardEvent) {
...
.
} else if (event.keyCode == 70) {
  fireBullet();}
..
}

public function fireBullet():void
{
   var heroP:Point = new Point(hero.mc.x, hero.mc.y);
   var bullet:Bullet = new Bullet(heroP.x, heroP.y, playerDirection);
  heroP = localToLocal(hero.mc, this, heroP);
  addChild(bullet);
trace(hero.mc.y);
  trace("addChild Bullet");
  bullet.addEventListener(Event.REMOVED, bulletRemoved);
  bulletList.push(bullet);
}

public function localToLocal(from:DisplayObject, to:DisplayObject, origin:Point😞Point
{
   if (!to || !from) return new Point();

   return to.globalToLocal(from.localToGlobal(origin));
}

In my Bullet.as

public function Bullet(heroPX:int, heroPXY:int, playerDirection:String) {
  trace("bullet called");
   // constructor code
   if(playerDirection == "left") {
  speed = -30; //speed is faster if player is running
  x =  heroPX;
   } else if(playerDirection == "right") {
  speed = 30;
  x =  heroPX;
   }
  y = heroPXY;

  trace(heroPXY);

  initialX = x; //use this to remember the initial spawn point
  addEventListener(Event.ENTER_FRAME, loop);
   }

The result for trace(heroPXY) and trace(hero.mc.y) are exactly the same ! So why the bullet is not aligned ?? (especially when y>160)

(here's a video of the problem if I haven't been clear: View" rel="nofollow">http://fr.tinypic.com/r/2cx7rqx/8]View My Video )

Source File : WeTransfer

Thx for your help !