Bottom line you did pretty good. One other helpful comment. Anytime I've ever wanted a plate number for future reference I have always concealed that act. I don't want anyone to take note of me taking note. Typically I just walk by and simply act like I forgot something, do a 180-degree turn and head back to where I came from. Sometimes I'll type the plate into my cell phone. Sometimes I'll call my own voicemail and just talk to it leaving a description of the car, identifying features and of course the plate right as I walk by it!
Janq: Strictly my opinion but I don't think I'd take chances with pepper spray being that there are 2 aggressors and 1 of me. You might spray one but the other's gonna be on you by that time. The OC doesn't deter that 2nd person the way a firearm does.