Ok, don't panic yet! This is a long list of things but try them and see if you can get it to work:
-make sure that you've updated your drivers to latest version
-Do a repair install of the game in Origin. In origin right click your game and from drop down choose repair install.
Do these too:
-Reinstall C++ redistributables.
1:go to C:\Program Files (x86)\Origin Games\Battlefield 4\__Installer\vc\vc2012Update3\redist
2: Double click vcredist_x64.exe/ vcredist_x86.exe and follow onscreen prompts.
-Update your Microsoft .NET framework.
http://www.microsoft.com/en-us/download/details.aspx?id=17851
Check now if you can play single player at least.
-Run the game as ADMINISTRATOR. (right click on the BF4.exe and select RUN AS ADMINISTRATOR)
-Disable Origin in game.
In Origin - Application settings - Origin in Game - disable Origin in game
-Try running the game in Windows compatibility mode.
C:\Program Files (x86)\Origin Games\Battlefield 4 > Right mouse click bf4.exe > scroll to 'properties' . Choose 'Compatibility' and select from options.
-Uninstall and Reinstall Origin. https://help.ea.com/article/manually-uninstalling-origin
If multiplayer still not working then:
-Reinstall Punkbuster.
Go to C:\Program Files (x86)\Origin Games\Battlefield 4 and select pbsv.exe . Choose 'reinstall'
Install advice for Punkbuster https://help.ea.com/uk/article/punkbuster-technical-issues
- Make sure you download and install the latest Battlelog plugins.
First uninstall old Battlelog plugin by going to "Control Panel\Programs\Programs and Features" and removing "battlelog web plugin".
Then log in using Origin and go to battlelog page where you'll be prompted to download latest web plugin.
After you have installed it you should clear your cache, exit your browser. Then restart your browser, and then re-login to Origin to ensure proper install.
If this doesn't work then you should try a different browser (Chrome/Maxthon/Firefox, etc)
- make sure that your firewall/anti virus isn't preventing the game, Punkbuster or Origin from launching.
Also check the quality of your internet connection.
I know its a long list of things to try but they might help you out. If they do then please leave a comment/XP point