Why do you feel so cold when your body temp is high from a fever---seems opposite?

Evaporation: When your body temperature is high, it tries to cool itself by opening capillaries near the surface of the skin. This brings the "warm" blood to the surface and increases evaporation. Evaporation causes the sensation of cooling. As an example, poor a small amount of rubbing alcohol on the back of your hand; as it evaporates, you will note a sense of cooling to that area.