Hi @rafaelzenato,
Sorry if I was unclear in my previous comment, this code will not fix anything, it should just create debug.log file inside your wp-content folder.
And it’s indeed created and there’s this fatal error showing up there:
[25-Nov-2016 10:55:59 UTC] PHP Fatal error: require_once(): Failed opening required ‘/home/nosnagringa/public_html/wp-content/plugins/jetpack/class.jetpack.php’ (include_path=’/home/nosnagringa/public_html/wp-content/plugins/google/lib/external/google:.:/usr/lib/php:/usr/local/lib/php’) in /home/nosnagringa/public_html/wp-content/plugins/jetpack/jetpack.php on line 71
It looks like the issue is related to Jetpack so to get back to your admin area you should access your WP files via FTP and remove the jetpack folder, after that you can try reinstalling it and if the issue is back again perhaps it would be best checking with their developers about this error.
Once you’re done with debugging and fixing this issue I suggest reverting your wp-config.php changes and deleting debug.log file from your wp-content folder.
Cheers,
Predrag