Internal:

Internal temperature is the person’s feeling that the body is very hot, despite the thermometer in the demon and the temperature increase, in these cases the person may have the same symptoms as a real fever, such as discomfort, chills and cold sweats, but the thermometer still regulates a temperature of 36 to 37 degrees […]

Internal fever is the person’s feeling that the body is very hot, even though the thermometer shows no temperature increase. In such cases, the person may have the same symptoms as in the case of a real fever, such as discomfort, chills and cold sweats, but the thermometer remains between 36 and 37 degrees Celsius,