I fell asleep on the sofa, and when I woke up, my neck hurt, and it hurt to eat

Stiff neck. The easiest and most practical way to stiff neck is:

a rolling pin, no limit on size or thickness;

Find a family member to hold the two ends of the rolling pin with both hands, stand behind you in the middle position, and scrape diagonally down from the back of the head from the parallel position of the ear to the end of the shoulder, three times in a row, with even force, which side of the stiff neck scrapes; It works very well and can give it a try. (similar to a gua sha action).

It should be the wrong sleeping position.