UI cycling through my level select levels

When I run my unity 5 game, it quickly cycles through all of my levels, then stops on my last level. My script for starting the levels is:

using UnityEngine;
using System.Collections;
using UnityEngine.SceneManagement;

public class Normal : MonoBehaviour {

    public void Start()
    {
        OnClick();
    }

    void OnClick()
    {
        SceneManager.LoadScene(1);
    }
}

I didn’t change anything from the basic UI menu that Unity has provided (I guess I did though, on accident). Here is the stuff that is attached to my UI buttons:


I do think there is an easier way to do this that works. I can clarify if needed. Thanks.

“Start” method runs as soon as a level is loaded.
Remove the Start method or just the call to OnClick() in the Start method.
Make OnClick() a public method and call that from the Button component’s On Click event.