I was thinking the same thing in fact. But my understanding from the DVD was that Justin wasn't exactly sure what caused the bleeding. It may have been cut earlier and started bleeding again due to some physical aggravation which broke the skin or may have been due to blood pressure.
Markus Ruhl's nose started bleeding like crazy during one workout and he said it was due to a nasal spray he had overused. Ryan Kennelly's EYES started bleeding during a lift in Chris Mason's "Road to the Arnold" DVD. 
If it was from a broken blood vessel, it would be from the blood pressure during the lift. Nothing you can do about that, your blood pressure is going to go up when you're training heavy.
But, with two little kids, and a wife, I do take care of myself with check ups. I work in a hospital, so I have full access to anything I need.
I get blood work ever 3-6 months (just have to walk over to the lab), and I perform echocardiograms and ECG's on myself from time to time.
It is my belief that blood pressure is the biggest nemesis to bodybuilders. Blood pressure is something that can EASILY be controlled, and is likely the cause of many of the problems bbers have, health wise.
Blood pressure can be controlled easily through diet changes, or medications......if the hypertension causes kidney failure....that cannot be controlled.
