I woke up with body and stomach cramps and a mild temperature ... oh oh . So I basically ate nothing and spent the day in bed . It proved the right strategy because 24 hours later I was much improved ! In retrospect I had the virus for a couple of days and the muscle pains were part of what made the bed uncomfortable .
According to the above context, answer the following question.
Why is the narrator potentially sore ?


They are suffering from a flu .