Tap to move Top Down 2D not working

So I was trying to copy some code from a tutorial (if anyone has any good C# tutorials as well that would be nice). The tutorial I was following is here http://unity3d.com/learn/tutorials/modules/beginner/live-training-archive/top-down-2d and all the code can be seen at 19.10ish I followed the tutorial every step but my code doesn’t work, and I would also like to make it work on a touch screen so will it it need changing or will it just assume the place im touching on the screen is the mouse? Sorry I know this is a lot of questions but I have been trying for about 2 days now.
Here is my code im using:
I cant see anyway they are different,
using UnityEngine;
using System.Collections;

public class PlayerMobility : MonoBehaviour {
public float speed;

void FixedUpdate()
{
	var mousePosition = Camera.main.ScreenToWorldPoint (Input.mousePosition);
	Quaternion rot = Quaternion.LookRotation (transform.position - mousePosition, Vector3.forward);
		
	transform.rotation = rot;
	transform.eulerAngles = new Vector3 (0, 0, transform.eulerAngles.z);
	rigidbody2D.angularVelocity = 0;

	float input = Input.GetAxis ("Vertical");
	rigidbody2D.AddForce (gameObject.transform.up * speed * input);
	}

}

it just seems to be the last little bit not working as the player rotates to the mouse correctly.

If you are using a sprite (as you indicate in your follow-up comment) then your rotation code is wrong. Change your sprite so that the front side is facing right. Then you can use this modified code:

using UnityEngine;
using System.Collections;
public class PlayerMobility : MonoBehaviour {

	public float force = 3.5f;
	
	void FixedUpdate()
	{
		Vector3 objectPos = Camera.main.WorldToScreenPoint (transform.position);
		Vector3 dir = Input.mousePosition - objectPos;
		float angle = Mathf.Atan2 (dir.y, dir.x) * Mathf.Rad2Deg;
		transform.rotation = Quaternion.AngleAxis (angle, Vector3.forward);

		rigidbody2D.angularVelocity = 0;
		
		float input = Input.GetAxis ("Vertical");
		rigidbody2D.AddForce (transform.right * force * input);
	}
}