just go to the local police station and tell them what happened and they will be able to find out if it was an unmarked car that pulled you over.
Personally if I wasn't sure it was a police car, I would call 000 and head for the nearest police station, and not pull over until 000 confirmed they were legit.
Just as a btw, the car that blocked me in from the rear when some guys tried to carjack me a while ago, was also a Hilux, but I'm pretty sure it was an older model.