Well, to be fair, dumbbell training is a lot more dangerous at heavy weights than barbell training is because with barbells, there's a lot that equipment like a power rack can do for you. It's probably not the presses messed you up, it's getting the dumbbells into position, getting them off and back onto the rack, that sort of thing. You can't just lower them onto pegs after your set is over.
Possibly. I had pretty good form with the whole off-the-knee kick-off to shoulder position. The muscle damage could have happened at any place throughout the movement. The massive weight and lack of range of motion definitely caused it.
In any case, large amounts of weight, and the tiniest deviation from form, lift-off, etc, will cause such hardship later in life that with some exercises, it's just not worth it to do small rep sets with heavy weight. The gains don't equate to the risk.
