What does it mean if my voltage regulator is acting as a wire?
Yes, it's probably burned out.

If you don't have the proper capacitors attached to the input and output, it's possible weird things will happen, but 90% chance it's just fried.

Make sure to take a look through the datasheet, and ensure that you're not exceeding any of the absolute maximum ratings. Also if there's an application circuit that shows the caps, try to copy those.