Unity Update() Function causing a NullReferenceException that isn't there if I manually call the function

Question

I have a pretty "basic" combat class here. It has a Player and an Enemy. They are inherrited from a Character class and have values such as health, armor and ar (attack rating (damage)). I am trying to set the combat up in a way so that once you press a button (in this case, e), you attack the enemy and the enemy attacks you. I think this is most easily done by having a method in Update() which constantly checks whether or not my desired key is pushed, and if it is, to execute said method which has 2 attacks. I have rearranged the program so that the Player and Enemy are saved seperately in the methods "savePlayer" and "saveEnemy".

Relevant global objects:

   public Player Player;
   public EnemyCharacterCreator Enemy;

   public Player savedPlayer;
    public EnemyCharacterCreator savedEnemy;
    public Text[] savedArray;

My constructor:

public Combat(Player Player, EnemyCharacterCreator Enemy, Text[] texxtArray)
    {
        savePlayer(Player);
        saveEnemy(Enemy);
        saveTextArray(texxtArray);
        textChanges();
     // FightLoop();
}

Aforementioned methods:

 public void savePlayer(Player Player)
    {
       savedPlayer = Player;
    }

    public void saveEnemy(EnemyCharacterCreator Enemy)
    {
      savedEnemy = Enemy;
    }

Combat-related code:

public void attackButton()
    {
        if (Input.GetKeyDown("e") == true)
        {
            FightLoop();
        }
    }
    public void FightLoop()
    {
            PlayerAttack();
            EnemyAttack();
            textChanges();
    }

    public void PlayerAttack()
    {
        savedEnemy.health = savedEnemy.health - savedPlayer.ar;
    }

    public void EnemyAttack()
    {
        savedPlayer.health = savedPlayer.health - savedEnemy.ar;
    }

Conceptually this should work fine, except it doesn't. When I "manually" execute FightLoop() in the constructor (commented out in the first code block) it works and the enemies health is reduced by 45 (which is my players' ar value), yet when I put attackButton() into the Update() function I get a NullReferenceException whenever I press e. 1 The error leads to line 74, which is the only line within the PlayerAttack() method:

savedEnemy.health = savedEnemy.health - savedPlayer.ar;

I put a breakpoint there and the savedEnemy object was null. I have no idea why, it is a global object and it works perfectly when I do it "manually", without Update(). Help would be appreciated.

Error Message

Enemy object gets saved in savedEnemy

Filled