If string contains #mudder Add to the database

Hello all,

I am able to pull the last 4 tweets made by a user and add them to a database but I only want to add the last 4 tweets that have '#mudder' in.

this is what I have so far

MyTimeLine.php

<?php

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

class MyTimeLine {
/**
 * myTimeline PHP Script
 * This script gets a user's twitter timeline and returns it as a multidimension array
 * each array containing 'tweet, date and link' respectively.
 *
 * @author Opeyemi Obembe <ray@devedgelabs.com>
 * @copyright Copyright (c) 2010, devEdgeLabs.
 */

	var $count;
	var $feedUrl;
	var $username;
	
	//@params: twitter username, number of needed updates (20 max)
	function myTimeline($username, $count = 20)
	{
		$this->feedUrl = 'http://api.twitter.com/1/statuses/user_timeline/'.$username.'.rss';
		$this->count = $count > 20 ? 20 : $count;
		$this->username = $username;
	}
	
	function since($date)
	{
		$timestamp = strtotime($date);
		$seconds = time() - $timestamp;
		
		$units = array(
			'second' => 1,
			'minute' => 60,
			'hour' 	 => 3600,
			'day'	 => 86400,
			'month'  => 2629743,
			'year'   => 31556926
		);
		
		foreach($units as $k => $v)
		{
			if($seconds >= $v)
			{
				$results = floor($seconds/$v);
				if($k == 'day' | $k == 'month' | $k == 'year')
					$timeago = date('D, d M, Y h:ia', $timestamp);
				else
					$timeago = ($results >= 2) ? 'about '.$results.' '.$k.'s ago' : 'about '.$results.' '.$k.' ago';
			}
		}
		
		return $timeago;
	}
	
	// Returns a multidimentional array, each containg 'tweet, date and link' respectively
	function get()
	{
		// Append the count
		$url = $this->feedUrl;
		$url .= $this->count == 20 ? '' : '?count='.$this->count;
		
		// The http CURL thingy
		$curl_handle = curl_init();
		curl_setopt($curl_handle, CURLOPT_URL, $url);
		curl_setopt($curl_handle, CURLOPT_RETURNTRANSFER, TRUE);
		curl_setopt($curl_handle, CURLOPT_TIMEOUT, 10);//10 secs max
		$data = curl_exec($curl_handle);
		curl_close($curl_handle);

		// Some error? Return an empty array
		// You may want to extend this to know the exact error
		// echo curl_error($curl_handle);
		// or know the http status
		// echo curl_getinfo($curl_handle, CURLINFO_HTTP_CODE);
		if(!$data)	return array();
		
		// Some reformatting
		$pattern = array(
			'/[^(:\/\/)](www\.[^ \n\r]+)/',
			'/(https?:\/\/[^ \n\r]+)/',
			'/@(\w+)/',
			'/^'.$this->username.':\s*/i'
		);
		$replace = array(
			'<a href="http://$1" rel="nofollow">$1</a>',
			'<a href="$1" rel="nofollow">$1</a>',
			'<a href="http://twitter.com/$1" rel="nofollow">@$1</a>'.
			''
		);
		
		$tweets = array();
		$xml = new SimpleXMLElement($data);
		foreach($xml->children()->children() as $item)
		{
			$tweet = preg_replace($pattern, $replace, $item->description);
			$date = $this->since($item->pubDate);
			$permalink = $item->link;
			$tweets[] = array($tweet, $date, $permalink);
		}
		
		return $tweets;
	}
}
?>

index.php

$db_values = '';
$tweet_feeds = '';

$min = 0;
$to_time = strtotime(date("Y-m-d H:i:s"));
$from_time = strtotime($user_records[0]['FeedUpdatedDate']);
$min = round(abs($to_time - $from_time) / 60, 0);



if ($min > 10) {
    
    
    
    $sql = "select * FROM tweet_feeds";
    if (!$result = $db->query($sql)) {
        die('There was an error running the query [' . $db->error . ']');
    }

    if ($result->num_rows > 0) {
        $result->free();

        $sql = "Delete FROM tweet_feeds";

        if (!$result = $db->query($sql)) {
            die('There was an error running the query [' . $db->error . ']');
        }
    }

    foreach ($user_records as $user) {

        $mytimeline = new MyTimeLine($user['TwitterName'], 4);
        $timeline = $mytimeline->get();

        $index = 0;
        foreach ($timeline as $tweet) {

            if ($index > 4)
                $db_values .= "('" . htmlentities($tweet[0], ENT_QUOTES, 'UTF-8') . "','" . $tweet[1] . "'," . $user['ID'] . "),";
            $index++;
        }
    }

    //insert all records in database 
	
	if (strpos($db_values,'#mudder') !== false) {
	
    $db_values = substr($db_values, 0, strlen($db_values) - 1);

    $sql = "INSERT INTO tweet_feeds (TweetText,TweetTime,twitter_person_id) Values " . $db_values;

    if (!$result = $db->query($sql)) {
        die('There was an error running the query [' . $db->error . ']');
    }

    $sql = "UPDATE twitter_person SET FeedUpdatedDate = '" . date("Y-m-d H:i:s") . "' where ID > 0";

    if (!$result = $db->query($sql)) {
        die('There was an error running the query [' . $db->error . ']');
    }
	}

As you can see I have tried to add

if (strpos($db_values,'#mudder') !== false) {    
$db_values = substr($db_values, 0, strlen($db_values) - 1);

$sql = "INSERT INTO tweet_feeds (TweetText,TweetTime,twitter_person_id) Values " . $db_values;

to try and add only mudder to the database but it just seems to add any of them.

Can anyone hold?