The actual error is the missing / in your #!/usr/bin/perl. With what you have ie #!usr/bin/perl your *nix host OS will be looking for Perl at /home/your/cgi-bin/usr/bin/perl and won't find it ie without the leading / it is a *relative path to the perl interpreter*, not an absolute one.

The real issue is that you don't seem to know how to debug a CGI yet. There will be an error message to this effect in the logs. See CGI Help Guide for some useful tips. BTW you can get a header with print $q->header() when using CGI as you are.