levo - 5:01 am on May 11, 2012 (gmt 0)

I'm not sure whether it was good that my website returned a proper 404 or not

Well, I was nervous too, but Google states that "Generally, 404 errors don’t impact your site’s ranking in Google, and you can safely ignore them" and "... 404s are a perfectly normal (and in many ways desirable) part of the web. You will likely never be able to control every link to your site, or resolve every 404 error listed in Webmaster Tools..." on https://support.google.com/webmasters/bin/answer.py?hl=en&answer=2409439