Very scarey.
I have trained Martial Arts for 14 years, we do a lot of knife defence and to be honest I would suggest not opening the door. Drive away, while you can.
Remember the Kenneth Noye incident in 1996, the young lad got out the van and battered Noye, so Noye went and got a flick knife and killed him. Plus it doesn't need to be a knife, it could be a screw driver.
If you aren't training for it, then you will have less of a chance in a confrontation, the adrenalin will take over. Always walk away from a confrontation.
I am so glad you and your family are ok.