Several errors after 3.5 update

Hi there.

I just updated to 3.5 (mattlaw.ca) and the wp admin panel is royally screwed. I am in well over my head on this one.

I am pretty new to this so any advice would be appreciated.

Problems I have noticed:
– widgets and menu items not dragable
– nothing appears in the visual or text editor
– cannot upload media
– several other problems with general functionality of admin panel (screen options and help panels will not drop down)

Error messages from one of my posts in the admin panel:

GET http://mattlaw.ca/wp-admin/load-scripts.php?c=1&load%5B%5D=jquery,utils,plupload,plupload-html5,plupload-flash,plupload-silverlight,plupload-html4,json2&ver=3.5 403 (Forbidden) post.php:33

Uncaught ReferenceError: jQuery is not defined akismet.js:1

Uncaught ReferenceError: jQuery is not defined script.js:109

GET http://mattlaw.ca/wp-admin/load-scripts.php?c=1&load%5B%5D=admin-bar,jquery-ui-core,jquery-ui-widget,jquery-ui-mouse,jquery-ui-sortable,hoverIntent,common,schedule,wp-ajax-response,autosa&load%5B%5D=ve,jquery-color,wp-lists,quicktags,jquery-query,admin-comments,suggest,postbox,post,thickbox,underscore,shortcode,backbone,media&load%5B%5D=-models,wp-plupload,media-views,media-editor,jquery-ui-position,wp-pointer,word-count,editor,jquery-ui-resizable,jquery-ui-dragg&load%5B%5D=able,jquery-ui-button,jquery-ui-dialog,wpdialogs,wplink,wpdialogs-popup,wp-fullscreen,media-upload&ver=3.5 403 (Forbidden) post.php:33

Uncaught ReferenceError: jQuery is not defined post.php:1211

Uncaught ReferenceError: getUserSetting is not defined wp-tinymce.php:22

I have switched themes, deleted themes, deactivated plugins, cleared browser cache, etc …

Help.