Add force once when object is created

I thought that this would add force once as soon as the object was created, but what happens is that the object just falls to the ground. Am I not doing this right?

using UnityEngine;
using System.Collections;

public class Bullet : MonoBehaviour {

	public int damageAmount;
	public float speed;
	public float timeToLive = 0;

	// Use this for initialization
	void Awake () {
		rigidbody2D.AddForce(transform.forward * speed, ForceMode2D.Impulse);
		Destroy(gameObject, timeToLive);

Transform.forward is the Z axis.

Rigidbody2D’s don’t move on the Z axis.

Try transform.right instead.