It is difficult to fall asleep in cold weather.

First: it's cold. You took a big piss in the middle of the night and took away a lot of heat. It is difficult to recover for a while, which makes people chilling. Because of the cold, the next sleep is affected by this, and the nightmares are repeated.

Second: You go into chills before you have a fever. After the human body is infected by bacteria and viruses, the immune system begins to raise the body temperature. In the preparation stage before the body temperature rises, there is a period of chills, followed by fever, dizziness, muscle aches and other symptoms.