Custom Redirects Preventing login

I am using custom redirects (shown below) to take users to new login and register pages

add_action('init','yobd_reg_redirect');

function yobd_reg_redirect(){
  global $pagenow;
  if( 'wp-login.php' == $pagenow ) {
    if ( isset($_GET['action']) && $_GET['action']=='register') { ?>
        <script>

            window.location.assign("<?php home_url() ?>/create-an-account/");

        </script>
        <?php }
    else wp_redirect(home_url('/user-login'));
    exit();
  }
}

this all works except the login form which has a form action to wp-login.php (action="domain.com/wp-login.php"), but because it is redirecting from wp-login.php it won’t let the user login at all. I know this is really a messy way to do it, but my client’s theme already has other login/register pages which he doesn’t want to use as he wants email confirmation