Exercicio 11.1 registro.py nao cadastra e erro ao ver Perfis

Após concluir o exercício 11.1, meu registro.py é exibido normalmente para cadastro, porem não consigo acessar mais http://localhost:8000/, é lançado o erro demonstrado abaixo.

Também não consigo cadastrar nenhum usuario no meu registro.py ele sempre retorna dados inválidos, pelo que entendi o primeiro registro deveria ser aceito.

Erro ao acessar http://localhost:8000/

DoesNotExist at /
Perfil matching query does not exist.
Request Method:    GET
Request URL:    http://localhost:8000/
Django Version:    1.7.4
Exception Type:    DoesNotExist
Exception Value:    
Perfil matching query does not exist.
Exception Location:    /Library/Python/2.7/site-packages/django/db/models/query.py in get, line 357
Python Executable:    /usr/bin/python
Python Version:    2.7.10
Python Path:    
['/Users/silvanioduartedacruz/connectedin',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC',
 '/Library/Python/2.7/site-packages']
Server time:    Thu, 30 Jun 2016 13:37:44 +0000

forms.py

from django import forms 
from django.contrib.auth.models import User

class RegistrarUsuarioForm(forms.Form):

    nome = forms.CharField(required=True)
    email = forms.CharField(required=True)
    senha = forms.CharField(required=True)
    telefone = forms.CharField(required=True)
    nome_empresa = forms.CharField(required=True)

    def is_valid(self):

        valid = True

        if not super(RegistrarUsuarioForm, self).is_valid():
            self.adiciona_erro('Por Favor, verifique os dados informados.')
            valid = False

        user_exists = User.objects.filter(username = self.data['nome']).exists()

        if user_exists:
            self.adiciona_erro('Usuario ja existe.')
            valid = False

        return valid

    def adiciona_erro(self, message):
        erros = self._errors.setdefault(forms.forms.NON_FIELD_ERRORS, forms.utils.ErrorList())
        erros.append(message)

view.py

from django.shortcuts import redirect
from django.shortcuts import render 
from django.contrib.auth.models import User
from django.views.generic.base import View
from perfis.models import Perfil
from usuarios.forms import RegistrarUsuarioForm

# Create your views here.
class RegistrarUsuarioView(View):

    template_name = 'registrar.html'

    def get(self, request):
        return render(request, self.template_name)

    def post(self, request):

        form = RegistrarUsuarioForm(request.POST)

        if form.is_valid():
            dados_form = form.data

            usuario = User.objects.create_user(dados_form['nome'], dados_form['email'], dados_form['senha'])

            perfil = Perfil(nome=dados_form['nome'],
                            email=dados_form['email'],
                            telefone=dados_form['telefone'],
                            nome_empresa=dados_form['nome_empresa'],
                            usuario=usuario)
            perfil.save()
            return redirect('index')


        return render(request, self.template_name, {'form' : form})

registra.py

{% extends "base_usuario.html" %}

{% block body %}

    <form class="form-signin" action="{% url 'registrar' %}" method="post" >

        {% csrf_token %}

        <h2 class="form-signin-heading">Crie seu Usuário</h2>

        <input type="text" name="email" id="id_email" 
            class="form-control" placeholder="Email *" required>

        <input type="text" name="nome" id="id_nome" 
            class="form-control" placeholder="Nome *" required>

        <input type="text" name="senha" id="id_senha" 
            class="form-control" placeholder="Senha *" required>

        <input type="text" name="telefone" id="id_telefone" 
            class="form-control" placeholder="Telefone" required>

        <input type="text" name="empresa" id="id_empresa" 
            class="form-control" placeholder="Empresa" required>

        <hr>

        {% if form.errors %}

            <div class="alert alert-danger">
                <button type="button" class="close" data-dismiss="alert" aria-hidden="true">&times;</button>
                {{ form.non_field_errors }}
            </div>

        {% endif %}

        <button class="btn btn-lg btn-primary btn-block" type="submit" value="login"> Registrar</button>

    </form>

{% endblock %}

models.py

from django.db import models
from django.contrib.auth.models import User

class Perfil(models.Model):

    nome = models.CharField(max_length=255, null=False)
    telefone = models.CharField(max_length=15, null=False)
    nome_empresa = models.CharField(max_length=255, null=False)
    contatos = models.ManyToManyField('self')
    ususario = models.OneToOneField(User, related_name='perfil')

    @property    
    def email(self):
        return self.usuario.email

    def convidar(self, perfil_convidado):
        Convite(solicitante = self, convidado = perfil_convidado).save()

class Convite(models.Model): #implementa um relacionamento

    solicitante = models.ForeignKey(Perfil, related_name='convites_feitos') 
    convidado = models.ForeignKey(Perfil, related_name='convites_recebidos') 

    def aceitar(self):
        self.convidado.contatos.add(self.solicitante)
        self.solicitante.contatos.add(self.convidado)
        self.delete()