Moved blog to subdirectory.. and now everything's crashing, can't log in

Hi all, I’m in a right panic at the moment, and I really home some of you kind folks can help.

So I took over the website for an annual school project this year. The address is gofar.sg, and I want to create a subdirectory for this year, gofar.sg/bhutan and copy ALL of the content from the main site over to the subdirectory.

So I create the subdirectory, and install WordPress, login, all’s fine.

Then I follow the instructions to move WordPress here (http://codex.wordpress.org/Moving_WordPress). Under the settings of the MAIN site, I change the WordPress address (URI) and Site address (URL) to gofar.sg/bhutan. I click save, and I get logged out of the admin page and asked to login to /bhutan/wp-admin page, which I’d already created.

I login, and then I copy all the files under home/public_html on my cpanel into the public_html/bhutan folder, where I’d just installed the WordPress.

I then try logging in again, and I get this “
Fatal error: Cannot redeclare get_query_template() (previously declared in /home/gofar/public_html/bhutan/wp-includes/theme.php:744) in /home/gofar/public_html/bhutan/wp-includes/template.php on line 30″.

I can’t log in now, and my main login at gofar.sg/wp-admin redirects me to gofar.sg/bhutan/wp-admin, which of course leads to the error above.

I now can’t log in at all, and I’m stuck. I am beside myself at the moment. Will someone please, please help?