I can't access my WP dashboard

I have a BuddyPress/Multisite WP site and am slowly trying to figure out how to configure it. I have a few questions about it but will leave those for now, because I can't even access my dashboard!

I had downloaded a bunch of WPMUdev plugins and batch activated them for my site. It asked me to add the RSS to my GoogleReader, which I thought was odd but did it as I've done many times. Now, whenever I try to go to my main site (www.cambriaequine.com) or the dashboard, I get an error:
https://cambriaequine.com/wp-admin/

I can access my test multisite (http://cambriaequine.com/test123/) and dashboard that does not have the plugins activated.

How do I get into my main site? It seems completely blocked off!

Thank you,
Hannah