Help with Wordpress 3.4 Upgrade

I tried automatically upgrading my website to Wordpress 3.4 and got the following error messages. When I try to access wp-admin: Fatal error: Class 'WP_Theme' not found in /home/bglhonl1/public_html/wp-includes/[login to view URL] on line 106 When I try to access my front page: Fatal error: Call to undefined function get_front_page_template() in /home/bglhonl1/public_html/wp-includes/[login to view URL] on line 26 I tried uploading the Wordpress 3.4 files manually to my server and I kept getting the error messages. I deleted my Quick Cache plugin and still got the error messages. I tried going back to the Wordpress 3.3.1 but the files didn't upload to my server. I am SO upset right now. Very frustrated. Need someone who can work quickly and communicate well.