I had this happen to a friend of mine....a couple of hillbillies in a pickup truck. He didnt know them and had never seen them before. They did exactly what you describe only they were throwing beer bottles at him too.
I would guess in your case they were likely drunk as well. He pulled into a well lit shopping mall and dialed 911 WHILE RIDING. Not the best of choices, but sometimes you gotta do what you gotta do.
Personally, I carry a .45 wherever I go. If that option isn't for you, I would suggest doing what my buddy did, and riding to a well lit area and dialing 911, or do exactly what you did this time.
Keep your distance and stay safe. But dont worry about it....like everyone said, it will probably not happen again. And karma will take care of them.
