Fatal error from custom plugin

Alright, so I’m making a basic plugin to learn how to create a custom widget.

I was following the format of a tutorial online because I found the codex to be somewhat unhelpful.

I downloaded my plugin (it’s a simple one that displays the name of three buildings from user input for now, I’ll add more later), I activated it, and now whenever I try to get on to my development site I get “Fatal error: Class ‘wp_my_plugin’ not found in /home/recreat/public_html/dev/wp-includes/widgets.php on line 413” on a white screen. No links, no other text, nothing.

I know exactly what I did wrong: When following the tutorial, I forgot to change “wp_my_plugin” in “add_action(‘widgets_init’, create_function(”, ‘return register_widget(“wp_my_plugin”);’));” (widget register line) to the name of the class of my file (in this example it’s “Hours_of_Operation”.)

I can’t go back, I can’t access anything else. I did a brief google search for more information or to see if I could go back to my site before the plugin was activated and found nothing.

Can someone point me in the right direction or help me out?

Thanks.