What illnesses are going around now and how long do they last? i have had flu symptoms, but no fever for 4 days.

Depends on location: Depending on where you live and what you are exposed to on a daily basis, you at greater or lesser risk for certain viral illnesses that tend to migrate across geographic areas. Sounds like you has a moderate viral illness. Probably will never know exactly what virus it was -- and that usually doesn't matter. Certain infections do have seasonality.