Twitter OAUTH and Codeigniter - codeigniter

Question

I'm trying to display tweets on a website built on codeigniter but can't seem to pull in the user tweets. To do this, I'm pulling the following script into my header as an include and then printing the tweet in the appropriate section with the code below. I've already set up the access tokens and consumer keys as well. Any ideas on why this is working?
Include file in header
<?php
function buildBaseString($baseURI, $method, $params) {
$r = array();
ksort($params);
foreach($params as $key=>$value){
$r[] = "$key=" . rawurlencode($value);
}
return $method."&" . rawurlencode($baseURI) . '&' . rawurlencode(implode('&', $r));
}
function buildAuthorizationHeader($oauth) {
$r = 'Authorization: OAuth ';
$values = array();
foreach($oauth as $key=>$value)
$values[] = "$key=\"" . rawurlencode($value) . "\"";
$r .= implode(', ', $values);
return $r;
}
$url = "https://api.twitter.com/1.1/statuses/user_timeline.json";
$oauth_access_token = "ACCESS TOKEN HERE";
$oauth_access_token_secret = "ACCESS TOKEN SECRET HERE";
$consumer_key = "CONSUMER KEY HERE";
$consumer_secret = "CONSUMER KEY SECRET HERE";
$oauth = array( 'oauth_consumer_key' => $consumer_key,
'oauth_nonce' => time(),
'oauth_signature_method' => 'HMAC-SHA1',
'oauth_token' => $oauth_access_token,
'oauth_timestamp' => time(),
'oauth_version' => '1.0'
);
$base_info = buildBaseString($url, 'GET', $oauth);
$composite_key = rawurlencode($consumer_secret) . '&' . rawurlencode($oauth_access_token_secret);
$oauth_signature = base64_encode(hash_hmac('sha1', $base_info, $composite_key, true));
$oauth['oauth_signature'] = $oauth_signature;
// Make Requests
$header = array(buildAuthorizationHeader($oauth), 'Expect:');
$options = array( CURLOPT_HTTPHEADER => $header,
//CURLOPT_POSTFIELDS => $postfields,
CURLOPT_HEADER => false,
CURLOPT_URL => $url,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_SSL_VERIFYPEER => false);
$feed = curl_init();
curl_setopt_array($feed, $options);
$json = curl_exec($feed);
curl_close($feed);
$twitter_data = json_decode($json, false);
$latest_tweet = $twitter_data[0];
?>
Print tweet
<span class="tweet">"<?php if(!empty($latest_tweet)){echo $latest_tweet->text;} else{echo "Welcome to Time Equities!";} ?>"</span>