Jumping and shooting knocks character off balance

Whenever I start shooting, everything works out fine (the bullets come out, they go in a certain direction.) But for some reason when my character is in the air and fires, the bullet seems to hit him and he starts spinning.

Code (csharp):

1.  
2.  
3. using System.Collections;
4. using System.Collections.Generic;
5. using UnityEngine;
6.  
7. public class BulletCtrl : MonoBehaviour {
8.  
9.     public Vector2 bulletspeed;
10.  
11.     [SerializeField]
12.     private float delay;
13.     Collider2D myCollider;
14.     Rigidbody2D rb2d;
15.     Collider2D coll;
16.     // Use this for initialization
17.     void Start ()
18.     {
19.         coll = GameObject.FindGameObjectWithTag ("Player").GetComponent<Collider2D> ();
20.         myCollider = GetComponent<Collider2D> ();
21.        
22.         rb2d = GetComponent<Rigidbody2D> ();
23.         rb2d.velocity = bulletspeed;
24.         Destroy (gameObject, delay);
25.     }
26.    
27.     // Update is called once per frame
28.     void Update ()
29.     {
30.         rb2d.velocity = bulletspeed;
31.         Physics2D.IgnoreCollision(coll, myCollider, true);
32.  
33.  
34.     }
35.  
36.  
37. }
38.  
39.  

Thanks for taking a look at my problem.

 

Do the IgnoreCollision in Start or Awake. You only have to call it once.

 

After doing that, the bullet still seems to collide with the character.

EDIT: I got it working somehow, but I'm not really sure how.