You can give a try to fix your problem using Recovery Mode(Safe Mode) if nothing helped

Hopefully your keyboard works in Recovery Mode.

• When your system starts chose Recovery Mode (2nd option in grub menu).


• From the Menu just go to Grub option, it will give a message like Updating grub will mount your system in read/write mode. Choose yes to mount your system in read/write mode. It will update your grub and will exit from Grub menu.


• chose network option, it may enable your network (it could take some time.).


• Then chose dpkg menu from the list, chose yes for all.



• Finally choose root option and log in. Execute the following commands one after another:

  
  
  

  apt-get autoremove
  
  apt-get autoclean
  
  apt-get update
  
  apt-get -f install
  
  apt-get dist-upgrade
  
  apt-get upgrade
  
  

  
  
  

  Also try to remove those package that you installed and caused such problems if you remember their names. Use these commands to remove:

  
  
  

  apt-get autoremove your_package_name
  
  apt-get --purge remove your_package_name
  
  

  
  
  

  Then again repeat above mentioned 6 commands.
  Then reboot your system and check whether your are able to use Ubuntu or not. Run this command to reboot:

  
  
  

  reboot