Rotate a thrown spear to Mouse Position (2d top down game)

Hello,

I want to rotate the top of a thrown spear to the mouse´s direction.

Thats my code so far. it rotates but not the way i want it to ... im new at coding and seriously need help please. im sitting on it for hours ... :(

(void throwSpear() is executed in another Script)

using System.Collections; using System.Collections.Generic; using UnityEngine; [RequireComponent(typeof(Rigidbody2D))] public class SpearThrow : MonoBehaviour {

 [SerializeField]
 private float speed;
 private Rigidbody2D myRigidbody;
 private Vector2 direction;
 private float throwingTime = 2;
 private bool spearThrowing = false;
 private float spearThrown;
 
 // Drag Spear Prefab to SpearThrow Script
 [SerializeField]
 private GameObject spearPrefab;
        

 // Use this for initialization
 void Start () {
     

     myRigidbody = GetComponent<Rigidbody2D>();

     // Throw spear To mouse position 
     direction = Camera.main.ScreenToWorldPoint(Input.mousePosition) - transform.position;        
     float angle = Mathf.Atan2(direction.y, direction.x) * Mathf.Rad2Deg;
     Quaternion rotation = Quaternion.AngleAxis(angle, Vector3.forward);
     transform.rotation = Quaternion.Slerp(transform.rotation, rotation, speed * Time.deltaTime);
     
 }

 private void FixedUpdate()
 {
            myRigidbody.velocity = direction * speed;

     if (Time.time > spearThrown + throwingTime && spearThrowing == true) 
     {                     
         Destroy(GameObject.FindWithTag("spear"));
     }

 }

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

     

 }


 public void throwSpear()
 {
    

     // Throw Spear
     
     Instantiate(spearPrefab, transform.position, Quaternion.Euler((Input.mousePosition) - transform.position));
     spearThrowing = true;
     spearThrown = Time.time;

 }
 

}