Kali Linux 2.0: Oh No, something has gone wrong. Need help.

[Dragonvarine]

I dual-booted Kali alongside Windows 7 and after typing: apt-get clean && apt-get update && apt-get upgrade -y && apt-get dist-upgrade, I decided I might as well install drivers, and I have Nvidia and I followed instructions on how to do it, and after typing: apt-get install -y linux-headers-$(uname -r) && apt-get install nvidia-kernel-dkms. I went to the next step: sed 's/quiet/quiet nouveau.modeset=0/g' -i /etc/default/grub
update-grub
reboot
After the reboot I get an error message saying "Oh No, something has gone wrong, the system is unable to recover" and clicking logout will just create a black screen that does absolutely nothing. Can someone help?
(I have a user created account as well if it's needed instead of the root account)
Thanks.