I have accidentally touched the 5V pin and GND pin together and the Arduino Uno has stopped working. What should I do now?
Remove ANYTHING connected to the board.
Re-boot your computer and see if you can upload a simple sketch such as BLINK
If it fails for any reason then just as she says buy a new one and dont do that again.
Could you take a few moments to Learn How To Use The Forum.
It will help you get the best out of the forum in the future.
Other general help and troubleshooting advice can be found here.