Destroying GameObject after amount of triggers

So i tried many things final code is here:
public class destroybycontat : MonoBehaviour {
public GameObject explosion;
public GameObject playerExplosion;
public int scoreValue;

 private GameController gameController;
 void Start()
 {
     GameObject gameControllerObject = GameObject.FindWithTag("GameController");
     if (gameControllerObject != null)
     {
         gameController = gameControllerObject.GetComponent<GameController>();
     }
     if (gameController == null)
     {
         Debug.Log("Cannot find 'GameController' script");
     }
 }

 void OnTriggerEnter(Collider other)
 {
     int i = 0;
     if (other.tag == "Boundary")
     {
         return;
     }
     Instantiate(explosion, transform.position, transform.rotation);
     if (other.tag == "Player")
     {
         Instantiate(playerExplosion, other.transform.position, other.transform.rotation);
     }
     if (other.gameObject.tag == "Enemy")
     {
         i = i + 1; 
         gameController.AddScore(scoreValue);
         if (i == 5)
         {
             Destroy(gameObject);
             Destroy(other.gameObject);

         }

     }
     gameController.AddScore(scoreValue);
     Destroy(other.gameObject);
     Destroy(gameObject);
 }

 

}

Look at the OnTriggerEnter method, i tagged a game object as" enemy" which includes a box collider with intrigger checked ,rigid body and a quad as a child .
As you can see im trying to count triggers to 5 and then destroy the object but lasers get him in the first shot,am im missing something...(class name missing letter i know)