show different messages inside a post on each time login,

add_action( 'wp_login', 'track_user_logins', 10, 2 );
function track_user_logins( $user_login, $user ){
    if( $login_amount = get_user_meta( $user->id, 'login_amount', true ) ){
        // They've Logged In Before, increment existing total by 1
        update_user_meta( $user->id, 'login_amount', ++$login_amount );
    } else {
        // First Login, set it to 1
        update_user_meta( $user->id, 'login_amount', 1 );
    }
}

add_shortcode( 'login_content', 'login_content' );
function login_content( $atts ){
    if( is_user_logged_in() ){
        // Get current total amount of logins (should be at least 1)
        $login_amount = get_user_meta( get_current_user_id(), 'login_amount', true );

        // return content based on how many times they've logged in.
        if( $login_amount == 1 ){
            return 'Welcome, this is your first time here!';
        } else if( $login_amount == 2 ){
            return 'Welcome back, second timer!';
        } else if( $login_amount == 3 ){
            return 'Welcome back, third timer!';
        } else {
            return "Geez, you have logged in a lot, $login_amount times in fact...";
        }
    }
}