PHP Login

session_start();
unset($_SESSION['badPass']);
//username and pasword sent from form
$myusername = $_POST['myusername'];
$mypassword = $_POST['mypassword'];
//Connect to server and select database
require_once 'DataBaseConnection.php';
//To protect MySQL injection
$myusername = mysql_fix_string($conn, $myusername);
$mypassword = mysql_fix_string($conn, $mypassword);
//hashed
$Hashed = hash("ripedmd128", $mypassword);

$sql = "SELECT * FROM Library.FandFamily WHERE UserName ='" . $myusername . "' and PassWord='" . $Hashed . "'";
$result = $conn->query($sql);

if(!$result) {
    $message = "Whole query " . $sql;
    echo $message;
    die('Invalid query: ' . mysqli_error());
}
//Mysql num_row is counting row
$count = $result->num_rows;

//If result moethod $myusername and $mypassword, table row must be 1 row
if($count == 1) {
    $_SESSION["something"] = "Yeah stuff";
    $_SESSION['user'] = $myusername;
    $_SESSION['password'] = $mypassword;
    //Register $username, $mypassword and redirect to file "Logn_success.php"
    header("Location: CodeExLoginSuccess.php");
        echo "Welcome";
    //echo"<a href='Catalogue.php'>To Shopping</a>";
} else {
    header("Location: CodeExLoginForm.php");
    $_SESSION['badPass']++;
    echo "Wrong username and password";
}
?>

***And here is the part of the form where it checks if the $_SESSION is set with isset()***

<form name="form1" method="post" action="CodeExLoginCheck.php" >
                <table align = "center" border="0" cellpadding="3" cellspacing="1" bgcolor="#FFFFFF">

                    <tr>
                        <td colspan="3"><strong>Member Login </strong></td>
                    </tr>
                    <tr>
                        <td width="78">Username</td>
                        <td width="6">:</td>
                        <td width="294"><input name="myusername" type="text" id="myusername" class="error"></td>
                    </tr>
                    <tr>
                        <td>Password</td>
                        <td>:</td>
                        <td><input name="mypassword" type="password" id="mypassword">
                            <?php
                                if(isset($_SESSION['badPass'])) {
                                    echo "<br> Username or password do not match";
                                }
                            ?>