Can't use DB Transactions in Controllers in laravel (DB::beginTransaction)

I have a DoctorsController which has a store method. I'm testing this method and I want my Models not to INSERT their data in testing environment. So I'm using DB::beginTransaction , DB::rollback() , DB::commit() methods in my controllers and my testing method to prevent INSERT queries. my problem is => Database is having records while my tests are running. I don't want any INSERTS during tests.

My test code :

public function testStoreMethod()
{
    /*
     * Test when validation fails
     */
    $data = include_once('DoctorsControllerFormData.php');

    foreach($data as $item){
        DB::beginTransaction();
        $response = $this->call('POST', 'doctors', $item);
        $this->assertResponseStatus(400, "response's HTTP code is not 400 : " . implode('\n',array_flatten($item)));
        Log::debug($response);
        DB::rollback();
    }
}

My DoctorsController code snippet : (which calls UsersController's store method)

public function store()
{
    //some code
    DB::beginTransaction();
    try{
        /*
         * User Creation
         */
        $user = new UsersController();
        $user->setResource('doctor');
        $userID = $user->store();

        //some other code
    }catch (InputValidationFailedException $e){
        DB::rollback();
        return Response::make(json_encode(array('error' => $e->getErrors())), \Symfony\Component\HttpFoundation\Response::HTTP_BAD_REQUEST);
    }catch(Exception $e){
        Log::error('Server Error at DoctorsController');
        DB::rollback();
        App::abort(500, $e->getMessage());
    }
}

My UsersController code snippet :

public function store()
{
    $user = new User;

    try{
        $inputs = Input::all();
        Log::info("input Data" . implode("\n", array_flatten(Input::all())));
        /*
         * User Creation
         */
        $v = Validator::make(
            $inputs,
            User::$rules
        );

        if($v->fails()) {
            Log::error('Validation Failed! ' . implode("\n", array_flatten($v->messages()->all())));
            throw new InputValidationFailedException($v);
        }
        $user->fname = Input::get('fname');//set first name
        $user->lname = Input::get('lname');//set last name
        $user->email = Input::get('email');//set email
        $user->cell = Input::get('cell');//set cell number
        $user->password = Hash::make(Input::get('password'));//set password
        $user->gender_id = Input::get('gender') == 'm' ? 1 : 0;//set gender
        $user->is_active = 0;//set activation status
        $user->role_id = ($this->resource == 'doctor') ? 1 : 2;
        $user->activation_time = 0;//set activation time default to 0
        $user->expiration_time = 0;//set expiration time default to 0
        //insert the user into DB
        $user->save();
    }catch (InputValidationFailedException $e){
        Log::info('User Validation Failed! ' . implode("\n", array_flatten($e->getErrors())));
        throw $e;
    }catch (Exception $e){
        Log::error('Server Error at UsersController!');
        throw $e;
    }

    return $user->id;
}

Thanks for your help.