Rails, Can't deploy app to heroku - ruby-on-rails

Question

I am new to rails, but got an app working great. Now I want to publish it to the web for a test. I am trying heroku, but can't get it to work.
Here is my gemfile:
source 'https://rubygems.org'
# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.2.4'
# Use sqlite3 as the database for Active Record
group :production do
gem 'pg'
end
group :development, :test do
gem 'sqlite3'
end
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5.0'
gem "font-awesome-rails"
gem 'carrierwave'
gem "rmagick"
gem 'responders', '~> 2.0'
gem 'prawn'
gem 'prawn-table'
gem 'bcrypt'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.1.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby
# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
#gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0', group: :doc
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'
# Use Unicorn as the app server
# gem 'unicorn'
# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development
group :development, :test do
# Call 'byebug' anywhere in the code to stop execution and get a debugger console
gem 'byebug'
end
group :development do
# Access an IRB console on exception pages or by using <%= console %> in views
gem 'web-console', '~> 2.0'
end
# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
And the error when doing the git push:
The thing is when doing the git push, it cannot install pg, tilt (it is not even in my gemfile, why does it even try?), and prawn, but mainly fails on pg.
I am doing this on a windows machine.
I got successfully to this part of the heroku guide for windows: https://devcenter.heroku.com/articles/getting-started-with-jruby#deploy-the-app
Then tried deleting the rails files and folders, and copying over the ones from my app, but it fails as shown above.
Thanks in advance for your help.