Can a gallbladder rupture without previous pain symptoms or without any injury?
It is not possible for a gallbladder to rupture without prior symptoms. Pain and tenderness in the abdomen should give you a signal. The pain is normally associated with vomiting, sweating and bloating. See http://www.mayoclinic.com/health/cholecystitis/DS01153/DSECTION=symptoms for more details.
Doubtful. Mine had perforations in it and wasn't ruptured yet and the pain leading up to that was unbearable.
I think NO. It can't rupture without any previous signs and symptoms.