Trouble storing value of drop down, and using in query - php

Question

Hi I am having trouble getting this to store the value when submitted and then using it in my next query. The drop down is populated fine, but it is either not storing the value or the way I am using it dynamically in my query is wrong. Any help is appreciated. I know I am probably missing something obvious or small, I am new to php.
drop down box
$sth = $db->prepare("SELECT DISTINCT WEEK FROM Player_Points_2013");
//$results = $stmt->fetchAll(PDO::FETCH_ASSOC);
$sth->execute();
echo '<form method="POST" action=" " >';
echo '<select id="week" name="week"><OPTION>';
echo "Select a Week to see the stats</OPTION>";
while ($row = $sth->fetch(PDO::FETCH_ASSOC))
{
echo "<option value=\"$WEEK\">" . $row['WEEK'] . "</option>";
}
echo '</SELECT>';
echo '<input type="submit" name="table_stats" value="Submit"/>';
echo '</form>';
$select_val = $_POST['week'];
//use value from drop down to display weeks stats
if(isset($_POST['table_stats'])){
$sql = $db->prepare("SELECT PName,CombinedPoints FROM `Player_Points_2013` WHERE
WEEK = '$select_val' ORDER BY CombinedPoints ");
//$results = $stmt->fetchAll(PDO::FETCH_ASSOC);
$sql->execute();
Print "<table border cellpadding=10 width=500>";
Print "<tr><th>Player</th><th>Points</th></tr>";
while ($row = $sql->fetch(PDO::FETCH_ASSOC))
{
Print " <td>".$row['PName'] . "</td> ";
Print " <td>".$row['CombinedPoints'] . "</td> </tr>";
}
Print "</table>";
}
else {
echo $select_val;
}
?>

Answer 1

Use either $row or $info but not both, e.g.:
while ($row = $sql->fetch(PDO::FETCH_ASSOC))
{
Print " <td>".$row['PName'] . "</td> ";
Print " <td>".$row['CombinedPoints'] . "</td> </tr>";
}
Also you have code:
echo "<option value=\"$WEEK\">" . $row['WEEK'] . "</option>";
What is $WEEK? Maybe it should be $row['WEEK'] instead?