Settings pages are created like this:
function pw_create_settings_page() {
global $pw_settings_page;
$pw_settings_page = add_options_page(__('My Plugin Settings', 'my-domain'), __('Plugin Settings', 'my-domain'), 'manage_options', 'my-page-slug', 'pw_callback_function');
}
add_action('admin_menu', 'pw_create_settings_page');