Constructor in controller is behaving strangely

[eluser]nagata[/eluser]

Code:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Admin extends CI_Controller {

    public function __construct()
    {
        parent::__construct();
        $user_email = $this->session->userdata('user_email');

        if(!empty($user_email)) {
        //logged in, do nothing, let the index load safely...
        } else {
           redirect("admin/login");
        }
    }

    public function index()
    {
        $this->load->view('admin/home');
    }

    public function login()
    {
       $this->load->view('admin/login');
    }
}

Its just Index is an initial page loaded if there is no function defined when u are going somewhere
ex: u have admin panel controller,
if u visit admin it will load by default the index()
if there was a function given it will then admin/(function)
...
u see...
it should do anything when user is logged in, if he isnt then just redirect him to login page...