Query doesn't insert into table - php

Question

I using a register form and i would like to see if i have missing columns/tables. I'm using var_dump $stmt; and echo $e->getMessage();
Every time I get successfully message but the code doesn't insert anything into the database .
If I'm using echo $e->getMessage(); I get this:
object(PDOStatement)#11 (1) { ["queryString"]=> string(153) "INSERT INTO bg_user(user_id, passwd, email, account_status) VALUES(:login, :password, :email, :status)" }
Notice: Undefined variable: e in include\classes\user.php on line 89
Fatal error: Uncaught Error: Call to a member function getMessage() on null in include\classes\user.php:89 Stack trace:
#0 include\functions\register.php(57): USER->register('test123', 'a3876fafbc8b9b9...', 'test#tex.com', NULL)
#1 pages\register.php(11): include('D:\Working Stat...')
#2 index.php(199): include('D:\Working Stat...')
#3 {main} thrown in include\classes\user.php on line 89
This is my code:
public function register($username,$password,$email,$ref)
{
global $safebox_size;
try
{
$password = md5($password);
$social_id = rand(1000000, 9999999);
$status = "OK";
$stmt = $this->account->prepare("INSERT INTO bg_user(user_id, passwd, email, account_status)
VALUES(:login, :password, :email, :status)");
$stmt->bindparam(":login", $username);
$stmt->bindparam(":password", $password);
$stmt->bindparam(":email", $email);
$stmt->bindparam(":status", $status);
$stmt->execute();
$lastId = $this->account->lastInsertId();
$safebox_password = "000000";
$stmt = $this->player->prepare("INSERT INTO safebox(account_id, size, password)
VALUES(:account_id, :size, :password)");
$stmt->bindparam(":account_id", $lastId);
$stmt->bindparam(":size", $safebox_size);
$stmt->bindparam(":password", $safebox_password);
$stmt->execute();
if($ref && count(getAccountInfo($ref)))
addReferral($lastId, $ref);
return $stmt;
}
catch(PDOException $e)
{
//echo $e->getMessage();
print 'ERROR';
}
}
My question is: what command do I have to use for var_dump, echo, print etc. to report errors (missing columns or tables)?