PHP MySQL在一个连接中运行两个查询

是否可以在一个连接中运行两个查询?我正在做的是我正在填充一个表单与配置文件数据。但随后我需要从包含值的数据库填充两个下拉列表。我已经包括了我如何设置，但我的第一个下拉菜单从来没有填充我做错了什么?

<?php
session_start(); 
include("includes.php");
$uid = $_SESSION[username];
    try
        {
            $con = mysql_connect("XXX.XXX.XXX.XX","ita","iiiii");
            if (!$con)
                {
                    die('Could not connect: ' . mysql_error());
                }
            mysql_select_db("bia", $con);
            $options = mysql_query("SELECT * FROM `Schools`");
            $options = array();
            while($row = mysql_fetch_assoc($options))
                {
                    $options[] = $row;
                }
            $result = mysql_query("SELECT * FROM `users` WHERE uid = '$uid'");
            while($row = mysql_fetch_assoc($result)){

?>
<form id="myform" name="myform" action="profiledo.php" method="post">
<p>First Name
  <input type="text" name="firstname" id="textfield" value="<?php echo( htmlspecialchars( $row['FirstName'] ) ); ?>" />
  <br />
<label for="collegedropdown"></label>
<select name="collegedropdown" id="collegedropdown">
<?php
  foreach($options as $option) {
      print '<option value='.$option.'>'.$option.'</option>'."'n";
    }
  }
?>
</select>