Locked myself out of the Dashboard :(

Silly me, locked myself out and can’t get back in to the dashboard.

I (stupidly it seems) in General_Settings changed the site url to https. And now can’t get back to …/wordpress/wp-admin.php. (each time I try the url changes to https:… which it can’t find!)

I read the FAQ “How do I reset the plugin’s settings?”
– And using FileZilla uncommented the line “//define(‘WPHTTPS_RESET’, true);”
– Saved the file (then checked it had saved OK)
– refreshed one of my pages
– commented back the line above and saved the file

But still can’t get the dashboard.
Have I misread/misused the FAQ instructions?
Any help, much appreciated.