Limping Rooster

I have a rooster that seems to have suddenly become very protective of the hens in my small flock of 6. One of the hens has just begun to lay eggs (the first of our flock). I was in the yard with my sons and the rooster waited until my 5 year-old son was alone and then attacked him! This was odd, because the kids go out in the yard daily and there has never been an incident such as this. My son was scared and began to scream as I ran over to him. The rooster has always been skittish around me or the kids, but even as I ran up to he and my son he stayed there attacking. Out of fear for my son and anger towards the rooster I gave the rooster a kick to get him away. The rooster ran away and appeared to be fine however, this morning he is limping and he isn't crowing (he generally crows all hours of the day). I'm afraid that I have inflicted injury to my rooster (for which I feel horrible), and am also afraid that he poses a danger to my children because of this act of aggression. Is he acting this way because my hen is laying eggs? At the moment of the incident, I was at the coop inspecting the nest and eggs with my other son. I don't believe my son provoked him at all, as my son has not done so in the past (and he claims that he hadn't been near the rooster or other chickens at all). I don't condone my action of kicking the rooster away from my son, but I suppose my reaction was much the same as that of the rooster protecting his offspring (if that was indeed the reason for the rooster to attack my son).

I've got a few questions:
1. Do I take my limping rooster to a vet, or do I wait to see if the limping/injury resolves itself?
2. Is this attack likely indicative of a new behavior that he has developed (will he continue this behavior as the hens are brooding)?
3. If I were to find a new home (or recipe) for my rooster, will my hen continue to be broody? Our intentions for the flock is to produce eggs for consumption, but we are hoping to experience hatching some chicks, too).