Did you use a pot or not?
The pot really is needed. It controls the amount of current supplied to your diode. To much current=dead diode.
This is actually a good video.
This is what you made...am I right?
You Killed your diode from to much current. It's a noob mistake. It happens to all of us. Buy/find another diode and give it a try again, except next time set the current to the proper levels first.