Game animation programming problem

Hi, I am kinda of a newbie to game programming even though, I am trying to make a game. I started by creating a character which can walk, attack, crouch and jump. I´ve been trying to make it as complete as possible so I made movie clips of it walking, attacking, jumping, falling,landing,etc. Everything is fine until it starts to descend after a jump. As I have said the character has an animation for jumping and falling. My character shows its animation when it is jumping but when it starts to fall it just shows the first frame of the movie clip of that animation. The same thing happens when it lands it just shows the first frame of the animation and then it returns to its standing position. So if anyoe can help me figure what is wrong with my code it would be really appreciated.
Here is the code, it is kinda of messy, sorry:

onClipEvent(load){
fight = false;
duck= false;
keydown = false;
falling = false;
gravity = true;
jumping = false;
jump = 0;
gravity = 4;
}
onClipEvent(enterFrame){
if(fight == false && duck == false && falling == false && jumping == false) {
if(Key.isDown(Key.LEFT) && fight != true && duck != true && falling != true && jumping != true){
this._x -= 4;
this._xscale = -100;
this.gotoAndStop(2);
}else if(Key.isDown(Key.RIGHT) && fight != true && duck != true && falling != true && jumping != true){
this._x += 4;
this._xscale = 100;
this.gotoAndStop(2);
}else if(Key.isDown(Key.DOWN) && fight != true && falling != true && jumping != true){
duck = true;
this.gotoAndStop(6);
}else{
this.gotoAndStop(1);
}
}
if(Key.isDown(Key.SPACE) && duck != true && keydown==false && falling == false && jumping != true){
this.gotoAndStop(4);
fight = true;
}
if(!_root.ground.hitTest(this. _x, this._y, true) && !jumping) {
_y+=gravity;
gravity=7;
falling=true;
}
if(Key.isDown(Key.UP)){
jumping = true;
}
if(jumping){
this._y-=jump;
this.gotoAndStop(11);
jump-=.5;
if(jump<0){
falling=true;
this.gotoAndStop(9);
}
if(Key.isDown(Key.LEFT)){
this._x -= 3
this._xscale=-100
}
if(Key.isDown(Key.RIGHT)){
this._x += 3
this._xscale=100
}
}
if(_root.ground.hitTest(this. _x, this._y, true) && falling){
jump=13;
this.gotoAndStop(5);
falling=false;
jumping=false;
}
if(this._currentframe == 1){
fight = false;
duck = false;
falling = false;
jumping = false;
}
if (Key.isDown (Key.SPACE)){
keydown=true;
}
else
keydown=false;
}

Thank you