Simple 2D Character Movement does not work properly

Hey guys!
Got a bug i cannot solve in my 2D character movement.

This is my code
public class Movement : MonoBehaviour {

    public Rigidbody2D rb;

    public float speed = 2f;

	void Start () {
        rb = GetComponent<Rigidbody2D>();
	void FixedUpdate () {
        float x = Input.GetAxis("Horizontal");
        float y = Input.GetAxis("Vertical");

        Vector2 vel = new Vector2(x * speed, y * speed);

        rb.velocity = vel;


This scripts is active on my character. My character has a Rigidbody2D (dynamic, mass and gravityscale = 1) and a box collider 2D,not changed anything so everything is quite standard.

Now when my movement script is active, my character seems to fall quite too slowly, as soon as i deactive it the character falls quite normale. I cannot see the reason for this behavior, but i am quite new to programming as well, so i do not know too much =D

I`ve tried to use different commands to move the character, but the problem was always the same

Thanks for any kind of help

If you are using the Physics/Rigidbody, then even in 2D you should not modify the y-value, but just copy it from the object you are about to move, like:

Vector2 vel = new Vector2(x * speed, transform.position.y);