I'm not sure if this will solve the issue you're having or not.  I'm a bit confused on what's happening to you, but it sounds like you set the SSL setting and didn't mean to.  Here's a SQL query that should reset the SSL settings to their defaults.  Run that query and then restart IIS or recycle your application pool.  This should make your Site Settings available again.

UPDATE [dbo].[PortalSettings] SET [SSLEnabled] = 'False', [SSLEnforced] = 'False';

or, if using Host > SQL...

UPDATE {databaseOwner}[{objectQualifier}PortalSettings] SET [SSLEnabled] = 'False', [SSLEnforced] = 'False';

Again, you need to recycle your application pool or restart IIS after you run the query, before you'll see it have any affect.