Procedural PHP to where?

<?php


if (isset($_POST['submitButton'])) {

    $db = new \mysqli("localhost", "user", "pass", "db");

    $user = new User("Juddling Stack", 123456);
    $user->setMoney(500.01);

    $player = new PlayerRegister($db, $user);

    if (! isset($_POST['money']) || ! is_numeric($_POST['money']))
        $player->addError("Enter Valid Wager Money");

    if ($_POST['money'] <= $user['money']) {
        $player->addError("You don't have that much money!");
    }

    try {
        $player->doSQL();
    } catch ( BaseException $e ) {

        foreach ( $e->getError() as $error ) {
            echo $error, " <br />";
        }
    }
}


/*******************
 *
 *
 *
 *  THE classes
 */


class Base {
    private $errors;

    function addError($error) {
        $this->error[] = $error;
    }

    function getErrors() {
        return $this->error;
    }

    function hasError() {
        return count($this->error) > 0 ? true : false;
    }
}


class BaseException extends Exception {
    private $error;

    function __construct(array $error) {
        $this->error = $error;
    }

    function getError() {
        return $this->error;
    }
}


class PlayerRegister extends Base {
    private $user;
    private $db;

    function __construct($db, User $user) {
        $this->db = $db;
        $this->user = $user;
    }

    function doSQL() {
        if ($this->hasError()) {
            throw new BaseException($this->getErrors());
        }
        $result = $this->db->query("SELECT * FROM someTable WHERE id={$user['id']}");
        $row = $result->fetch_assoc();

        if ($row) {
            /*
             * run some queries, give user some item
            */
        }
    }
}


class User extends Base {
    private $name;
    private $money;
    private $id;

    function __construct($name, $id) {
        $ths->name = $name;
        $this->id = $id;
    }

    function setMoney($money) {
        $this->money = $money;
    }

    function getName() {
        return $this->name;
    }

    function getMoney() {
        return $this->money;
    }

    function getID() {
        return $this->id;
    }
}


?>