Help! Not able to log in to my admin panel on my website

Hi.. Need some urgent help please!
I downloaded bbpress, and clicked activate and woah! from then i am not able to sign in to my admin page!
I need to update my website urgently and for some reason im not able to get into the admin panel. It says “The website encountered an error while retrieving. It may be down for maintenance or configured incorrectly.”
Whereas it is loading for another of my wordpress site.

Help Please!