depends on how much downtime you can afford. I would get a new axle installed and manually rotate it for any unusual signs. Drain the fluid & check for metal shavings or bearing parts. Worst case you put it back together now and drive it around a bit until something breaks.

Honestly you are lucky to be alive. The ball join dropping out of the knuckle could have ended up much worse for you... How did the nut back off? Have you ever removed it or done anything with that control arm?