Well, yes, it could mean frostbite, but it also probably means your furnace just can't keep you warm enough.
Many people turn to space heaters to help heat rooms they use most often.
The heaters help take the chill out of the air, while allowing the furnace to take a rest. Most space heaters can be safely used indoors, albeit with some caution. The size of the heater and how much heat it can produce will determine in what size room it will work best. Kerosene heaters have gotten less than favorable press since their introduction. Fires caused by kerosene heaters seem to reappear in the headlines during winter months.