Yah, for convenience's sake, let's say that Relentless Endurance can work like that. The attack sends you reeling, but on your initiative you can rise up from the ground. Note that this is both a positive and a negative thing: You may not end up burning the skill for nothing, but on the other hand you lose half your movement to stand up after being prone. Or if you'd like, when you are reduced to zero hit points you can just notify me and I'll change the storytelling accordingly. Whatever goes.

And yes, the commoners are seeking to keep their distance.