Pl do not worry about 19th May ticket. Your ticket is RAC. For 2 tickets, one berth (generally side lower) is confirmed. If vacant berth is available, full berth wll be allotted during journey. Half berth is - one berth (Side Lower) is allotted to two persons. Depending on vacancy & priority no. in RAC, other will also be confirmed. You can still travel by the train even if both berths are not confirmed. Your low rac no. will get confirmed before departure. happy journey