与类进行检查并停止脚本

我创建了一个脚本来更改用户的密码，但在检查时仍在继续。

class mudar_senha{
    protected $page_return = 'mudar_senha';
    private function encriptaSenha($senha) {    
            return base64_encode(pack("H*", sha1(utf8_encode($senha))));
    }
    private function query_senha(){
        global $_LANG;
            $user_id = $_POST['id_user'];
            $q=new Query;
            $q
                    ->select()
                    ->from('`usuarios`')
                    ->where_equal_to(
                            array(
                                    'id'=>$user_id
                            )
                    )
                    ->limit(1)
                    ->run();
            if($q){
                    $user=$q->get_selected();
                    return $user['senha'];
            }
            else{

            return 
                alerta($_LANG[165]);
                retornar(NULL,$this->page_return);  
                    die;    
            }       
    }
    private function verify_senha($senha){
        global $_LANG;
            if($this->encriptaSenha($senha) == $this->query_senha()){
                return true;    
            }else{

                return 
                    alerta($_LANG[203]);
                    retornar(NULL,$this->page_return);  
                    die;    
            }
    }
    private function verify_senhas(){
        global $_LANG;
            if($_POST['cpass1'] == $_POST['pass1']){
                return true;
            }else{
                return 
                    alerta($_LANG[171]);
                    retornar(NULL,$this->page_return);  
                    die;
            }

    }
    private function verify_length($senha){
        global $_LANG;
            switch($senha){
                case(strlen($senha) < 6) :
                    return $_LANG[206];
                        die;
                case(strlen($senha) > 11):
                return 
                    alerta($_LANG[205]);
                    retornar(NULL,$this->page_return);  
                    die;
                default:
                    return true;
            }
    }
    private function verify_caracteres($senha){
        global $_LANG;
            if(preg_match('/['''/~`'!@#'$%'^&'*'(')_'-'+='{'}'[']'|;:"'<'>,'.'?''']/', $senha)){
                return 
                        alerta($_LANG[204]);
                        retornar(NULL,$this->page_return);  
                        exit;
            }else{
                return true;
            }
    }
    final public function _build(){
        global $_LANG;
            if($this->verify_senha($_POST['req1'])      == true);
            if($this->verify_senhas()                   == true);
            if($this->verify_length($_POST['pass1'])    == true);
            if($this->verify_caracteres($_POST['pass1'])== true);
                $q=new Query;
                $q
                    ->update('usuarios')
                    ->set(
                            array(
                                            'senha'         =>  $this->encriptaSenha($_POST['pass1']),
                                            'pass_decode'   =>  $_POST['pass1'],
                            )
                    )
                    ->where_equal_to(
                            array(
                                    'id'=>$_POST['id_user']
                            )
                    )
                    ->limit(1)
                    ->run();
                        if($q){
                            alerta($_LANG[207]);
                            retornar(NULL,$this->page_return);
                        }else{
                            alerta($_LANG[165]);
                            retornar(NULL,$this->page_return);
                            exit;
                        }       
    }

}

$q = new mudar_senha;
$q->_build();

只有三张支票-密码正确吗？-密码正确吗？-密码长度-特殊字符

如果它拒绝检查，脚本将返回true，并且它执行build函数检查更改是否正常继续。