First, look at your bills. It should say "estimated" or "actual" on each one. Go out and read your meter, and compute your usage per day since the last actual reading. Maybe even read it each day for a few days, or several times a day to get a feel for when you use more/less kWh.
What runs on electric in your house? Heat, water heater, well pump, stove, dryer, freezer? Those are some of the bigger users, I'm sure there are others. Lights and small appliances generally don't use that much. We don't have any of the big users on my list (oil boiler w/ water heater, propane stove, none of the rest); our electric usage was 8 kWh per day on the most recent bill, and that's high for us, but the historic cold last month meant the heat ran near continuously, and we had electric heaters running to thaw frozen pipes, more than once! Could your place possibly have heat tapes on pipes to prevent freezing?