Read through
this and pay attention to the parts where he talks about vehicle ops and SHTF driving, part VI about half way down the page. There's some good info to be gleaned from that article.
You chose the wise course of action, which was keeping your head focused and knowing the priorities/protecting the Primaries ..Get off the X, then fight it out if need be.
Now hopefully you can clearly see how "action beats reaction" every time, how quickly a "scenario" can escalate beyond your control, how there might not be anyone else to help, and how situational awareness rules the day.
Weapons aren't always necessary but a sharp/trained/alert mind is.
I'm sure that there were things that you could've done differently, only you will know how to address those things in the future, chalk this one up in the "lessons learned" category and work on any weaknesses that you've identified from this encounter.
It definitely sounds like your .mil training helped you out on this one.
Take care.