My site was working fine until yesterday when I installed

My site was working fine until yesterday when I installed a few updates.

Then I started getting a white screen of death.

I turned on debug mode in wp-config.php.

I'm getting these errors when BuddyPress is activated:

Notice: bbp_setup_current_user was called incorrectly. The current user is being initialized without using $wp->init(). Please see Debugging in WordPress for more information. (This message was added in version 2.3.) in /home/MYUSERNAME/public_html/wp/wp-includes/functions.php on line 3049

Notice: bp_setup_current_user was called incorrectly. The current user is being initialized without using $wp->init(). Please see Debugging in WordPress for more information. (This message was added in version 1.7.) in /home/MYUSERNAME/public_html/wp/wp-includes/functions.php on line 3049

Fatal error: Allowed memory size of 104857600 bytes exhausted (tried to allocate 491520 bytes) in /home/MYUSERNAME/public_html/wp/wp-content/themes/canvas/functions/admin-functions.php on line 1969

Note that BuddyPress was not one of the plugins that was updated. I tried downgrading each of the plugins to previous versions, but I still get the white screen unless BuddyPress is deactivated.

I'm using WooThemes Canvas, FWIW.

I hope this is something you can help me with.

Thank you.