Admin interface not working

Hello there,

I was following a Drupal theme tutorial, ran into bad problems (white screen of death). I was able to get it to show something on my home page. I changed the default theme to Bartik in the settings.php file.

Now, the admin toolbar shows on top, but if I try going into appearance, configuration, or anything else, the white screen pops up again. I don’t know what to do. Any help would be appreciated!

I also get these listed errors on the hope page (they show up multiple times on the page, I just truncated it since it repeated itself:

Notice: Undefined index: devel_function_preprocess_intercept in devel_themer_theme_twin() (line 410 of /home/wigarden/public_html/sites/all/modules/devel_themer/devel_themer.module).
Notice: Undefined index: devel_function_process_intercept in devel_themer_theme_twin() (line 411 of /home/wigarden/public_html/sites/all/modules/devel_themer/devel_themer.module).
Notice: Undefined index: type in devel_themer_theme_twin() (line 480 of /home/wigarden/public_html/sites/all/modules/devel_themer/devel_themer.module).
Notice: Undefined index: template in devel_themer_theme_twin() (line 508 of /home/wigarden/public_html/sites/all/modules/devel_themer/devel_themer.module).
Notice: Undefined variable: suggestions in devel_themer_theme_twin() (line 515 of /home/wigarden/public_html/sites/all/modules/devel_themer/devel_themer.module).
Warning: include(/home/wigarden/public_html/.tpl.php): failed to open stream: No such file or directory in theme_render_template() (line 1525 of /home/wigarden/public_html/includes/
Warning: include(): Failed opening '/home/wigarden/public_html/.tpl.php' for inclusion (include_path='.:/opt/alt/php55/usr/share/pear:/opt/alt/php55/usr/share/php') in theme_render_template() (line 1525 of /home/wigarden/public_html/includes/
Drupal version: