OOC:
The extra damage is from Vicious 1, which gives 1 more damage per effect.
Damage and injuries basically work like the progress track of challenges, where the damage taken is progress, and injuries are breakthroughs.
You were injured because you took 5 damage, and once injured you have to spend a point of Determination if you want to participate further in the scene.
Alpha1.2Rules says:
An Injured character cannot attempt Tasks or perform Minor Actions, and is essentially no longer participating in the scene, unless that character spends one Determination to keep fighting. Spending a point of Determination here allows the character to keep fighting normally despite being Injured for the rest of the scene.
Recovering from Injury is another matter. If the Attack or hazard that inflicted the Injury was intended to Stun, then the Injury is recovered automatically at the end of the scene: the character regains consciousness without difficulty, though they may be in an awkward situation if the enemy managed to capture them in the process.
In this case, well.. I'm not sure what the little fellar was
intending to do, but I'm regarding this as a "Stun" injury. In any case you are knocked out for the rest of the scene unless you spend determination. "Treating" your injuries doesn't need a check, and is only a RP opportunity. I'm not completely certain on what constitutes a "scene" here, but I'm interpreting it to be until the task is done (little bugger' is caught).