You might try it again now ... while my sites were "up" I was having panel problems for the last few minutes, but the panel is now working well for me.
If you share your url others could see if they can display your site (and help determine if you are having connectivity issues or the site is just not responding).
Also, if you can't submit a support request via the panel, you can always use the form at http://dreamhost.com/contact.cgi to report your problem.
While it is not a good as using the support request system, your message will get through that way eventually.
Generally, if the Control Panel is down at all, the DH staff knows about it before you report it (they use the same panel constantly in their work).