Mecanim Drawer Animation problem?

I am trying to create a Dresser with drawers that when a key is taped open and when is taped again close, for this I used Mecanim, the animations runs properly but Mecanim passes trough my transitions all at once when I press the key once, it doesn't wait for me to tap the key again. My question is how can I make Mecanim after the first animation is played to wait until I tap the key again?

Here is my code:

public class Drawer : MonoBehaviour {

 int state;
 bool isClosed = false;

 Animator anim;

 // Use this for initialization
 void Start () {
     anim = GetComponent<Animator> ();
 }

 public void OnLookEnter ()
 {
     anim.SetInteger ("State", state);

     if (Input.GetKeyDown (KeyCode.E)) {    // Idle to open
         state = 1;
     }

     if (Input.GetKeyDown (KeyCode.E) && state == 1) { //Open to close
         state = 2;
     }

     if (Input.GetKeyDown (KeyCode.E) && state == 2) { // Close to open
         state = 3;
     }
 }

 // Update is called once per frame
 void Update () {
 
 }

}