Inserting values into a table with a PHP-variable name

I'm setting up a simple website where each user gets their own table (bad idea, I know), in which other users can put comments into - like a super budget version of a Facebook-wall.

This is what my query looks like when I create the table:

$userTable = mysqli_query($conn, "CREATE TABLE `".$epost."`(
        ID INT(255) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
        eMail VARCHAR(50) NOT NULL,
        comment VARCHAR(500) NOT NULL,
        timestampp TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
        )");

However, when I try to take the values from a form, and insert them into the specific table they can't seem to find their way in there. Here's my code of that:

    <?php

include 'connect.php';

/*if(isset ($_POST['userUser']))*/

$valueEmail = mysqli_real_escape_string($conn, $_POST['userEmail']);
$valueUser = mysqli_real_escape_string($conn, $_POST['userUser']); /*have the user to input the name, so i can connect to the correct DB*/
$valueMessage = mysqli_real_escape_string($conn, $_POST['userMessage']);

$findUserTable = "SELECT * FROM UserInfo WHERE Firstname = '$valueUser'";
$findUserEmail = mysqli_query($conn, $findUserTable);

if(mysqli_num_rows($findUserEmail) > 0) /*finding the name of the persons email*/
    {
        while ($result = mysqli_fetch_assoc($findUserEmail))
        {
            $email = $result['Email'];
        }
    }

/* VALIDATION HERE */

$sql = "INSERT INTO ".$email." (eMail, comment) VALUES ('$valueEmail', '$valueMessage')"; /* wrong query?*/

header("refresh:10 url=userProfil.php");
/*echo '<script>alert("Meddelande skapat!");</script>';*/

echo $sql;

mysqli_close($conn);

?>

I've been trying different 'versions' of the variable, like ".$email.", '.$email.' and ".$epost.". I get the correct name when i echo out my query or just the variable - but it can't seem to find the table? I'm very aware that my code smells badly, so please spare me on that point.

Solution

You just simply wrote your query and forgot to execute it:

$sql = "INSERT INTO ".$email." (eMail, comment) VALUES ('$valueEmail', '$valueMessage')"; /* wrong query?*/

To execute, use this:

mysqli_query($conn,$sql);//for execute

It'd be even better if you use bind and prepare statements:

$sql = "INSERT INTO ".$email." (eMail, comment) VALUES (? ,?)";
$stmt = $conn->prepare($sql);
$stmt->bind_param("ss", $valueEmail, $valueMessage);

/* Execute the statement */
$stmt->execute();
$row = $stmt->affected_rows;
if ($row > 0) {
    echo "data inserted";
} else {
    "error";
}