One of the joys of fencing is playing the "where did I get that bruise" game.
Way back when I first started fencing - not so much bruising since we were in classes and not super competitive. As soon as my group classes finished and I started fencing competitively I got lots of bruises.
As I progresses, less overall random bruising, but still a good bit on the upper arm, chest, and back of shoulder. The progression has been - as my fencing and my competitors get better, the bruises show up more in the target area than outside of it.
The big difference between the bruises that beginners and advanced fencers leave you with is their severity. A bruise from a beginner is more likely to be a "thwack" bruise (comes from them hitting you with as much blade as point) and bruises from advanced fencers all tend to be little circles from where their tip hit you.
You're right in that it always looks a lot worse than it feels. Often I would come home from practice (always intense bouting) and my wife would comment on all the bruises, most of which I had no idea were there; just didn't feel any of them.
Of course, the better you get the less bruises there will be since you'll be preventing them!
Cheers,
Craig