Brake lights not working, but running lights do

It has aftermarket under-glow which includes a ton of aftermarket wiring underneath the car. A few months ago, I borrowed my car to a friend for a night out and they ran over a construction barrier and shattered a under-glow bulb underneath the car. When this happened, obviously the under-glow stopped working completely. But along with this my dash lights and brake lights stopped working. The running lights work on the back but not the brake lights. The hazards and blinkers work also, but still no brake lights. I am just wondering what the problem could be?