I changed my BLOG address and now I cant change it back

I’ve done a search for this and I cont seem to find any answers. I cnaged my blog addressin the general option while playing with a plugin, now the whole site is messed up. Everything shows up but the theme is gone. I’m running it on a subdomain and I know that’s causing the problem. I can type the URL in manually to log in, but when I try to change the URL back I get that stupid enable referrers crap and I know it;s enabled on every browser I have. I also disabled my firewall.

Does anyone have an answer for this?