Can't log into Admin Panel net::ERR_EMPTY_RESPONSE

My blog is working, and you can check it out here: http://pleasepasstheketchup.ca.

I added a new post this morning but am now unable to log into the admin panel. Nothing else was changed, no plugins, no updates, nothing.

I’ve seen http://codex.ww.wp.xz.cn/Login_Trouble and the majority of this article does not apply to my site. Any suggestions?

I get the error net::ERR_EMPTY_RESPONSE in Chrome and “Zero Size Reply” in IE.

This is driving me crazy. I am able to log into the host back end cPanel. I have looked at the config files but programming is not my strong suit.

I need help, please and thanks!