Facebook API Giving Server error 500 - php

Question

I'm having a lot of trouble getting the Facebook API to work at all. Any example code I use gives me Server Error 500. I'm trying to post a link to my facebook page (this code is from the example code Facebook gives in its documentation). To clarify as well, I do have an app-id, secret-id, and I believe I got the right access token from the Graph API. I know I need a public_action permission to post a link, but the way I read it, I think the access token defaults with public_action.
<?php
$appid = '{app-id}';
$appsecret = '{app-secret}';
$redirect_uri = 'http://mywebsite.com';
// Define the root directoy
define( 'ROOT', dirname( __FILE__ ) . '/' );
// Autoload the required files
require_once( ROOT . 'facebook-php-sdk-v4-4.0-dev/autoload.php' );
$fb = new Facebook\Facebook([
'app_id' => '{app-id}',
'app_secret' => '{app-secret}',
'default_graph_version' => 'v2.2',
]);
$linkData = [
'link' => 'http://www.example.com',
'message' => 'User provided message',
];
try {
// Returns a `Facebook\FacebookResponse` object
$response = $fb->post('/me/feed', $linkData, '{access-token}');
} catch(Facebook\Exceptions\FacebookResponseException $e) {
echo 'Graph returned an error: ' . $e->getMessage();
exit;
} catch(Facebook\Exceptions\FacebookSDKException $e) {
echo 'Facebook SDK returned an error: ' . $e->getMessage();
exit;
}
$graphNode = $response->getGraphNode();
echo 'Posted with id: ' . $graphNode['id'];
?>
I really do not know what I am doing wrong. Likewise, where it says "me" should that be my facebook user id? Thank you.