For the directive error, this is most commonly caused by plugins. To test this, you will want to disable all existing plugins to see if the error goes away. If so, you want to re-enable each plugin one by one and see if the error occurs. Once it occurs, then you know which plugin is the culprit.
As for your domain name, that sounds like normal propagation. This usually takes 24-48 hours. Once that time period passes, you should no longer see that redirection behavior. It is likely a local dns server caching issue.