First, don’t name your threads “Help please”. This is a help forum. It won’t get your post answered any quicker. (And in fact, some people just automatically ignore any thread with such a title.) Stay calm and name your specific problem. Believe me, this is fixable.
Second, this is why you NEVER edit theme, WP, or plugin files, at least on an active site. Your best bet is to install AMP on a local host: WAMP, MAMP, XAMP. (Don’t ask; Google.)
Third, just ftp to your site, go to the plugins folder, and delete the plugin whose files you were editing. (As a side note, I’ve found WP’s built-in file editor to be completely worthless, entirely for reasons like this. It’s much better to edit files locally and then ftp them to your server.)