You have lots of variables here...
Propane tank size?
Heater tempature setting?
Do you turn down heater when not there?
Fridge/freezer temp setting?
Fridge/freezer full or loosely packed?
Were fridge/freezer items already cold when loaded in?
Water heater size/demand?
Do you turn down water heater when not in use?
Number of meals cooked?
Oven used or just stove?
Gas light use?
Insulation in walls?
Insulation on walls - bare aluminum walls (paint) or fabric covered?
Draperies on windows (insulation)?
All these & more make a difference...four days with small tanks and high demand doesn't sound too unreasonable in the winter months to me ~