void OnTriggerEnter2D(Collider2D col)
 {
     if (col.tag == "Player")
     {
         if (!ps.hasPowerUp)
         {
             ps.ActivatePowerUp(gameObject.name);
             GameManager.singleton.itemMaxCounter--;
             Destroy(gameObject);
         }
         else
         {
         }
     }
     else
     {
     }
 }