Is this energy cost normal?

My apartment is 108 sqm built in 1994. The energy rating of the apartment is B but I changed the gas stove to induction and my VVE changed the boiler which was installed 16 years back.

I turned on the living room radiator for 3-4 hours and then turned it off. The bedroom radiator was on for ~7 hours and the small radiator in the home office was on for ~8 hours. The thermostat temperature was set to 20 degrees. The total cost for the day seems to be very high. If I continue this way, I would end up paying over 500 for a month. Is this normal?