Move recaptcha validation

[tomharto]

I use recaptcha on my site but for some reason when i test my form if i leave it blank it doesnt spit back any error, and also i cant get it to validate before my form is checked.

This is the whole code for it which is currently in the middle of my form

//blahblah rest of the form up here
Enter Validation Code:<br /><br>
<?php
        require('recaptchalib.php');


        // Get a key from https://www.google.com/recaptcha/admin/create
        $publickey = "6LfKI8cSAAAAAHEAK9vir063pXncb72-kw_DVj3L";
        $privatekey = "6LfKI8cSAAAAAFOpgdi29sxTlhIck7t2ufB3YWOW";
        
        # the response from reCAPTCHA
        $resp = null;
        # the error code from reCAPTCHA, if any
        $error = null;

        # was there a reCAPTCHA response?
        if ($_POST["recaptcha_response_field"]) 
        {
            $resp = recaptcha_check_answer ($privatekey,
                                            $_SERVER["REMOTE_ADDR"],
                                            $_POST["recaptcha_challenge_field"],
                                            $_POST["recaptcha_response_field"]);
            if ($resp->is_valid) 
            {
                echo "You got it!";
            }
            else
            {
                # set the error code so that we can display it
                $error = $resp->error;
            }
        }
    
echo recaptcha_get_html($publickey, $error);
?>
//last of the form and submit button down here

I want to move the checking part to the beginning of my form so if there are any errors i can display before my form loads but i cant get it to work if i move anything, can anyone else?