and make sure that it is either a cold or a flu. if you start having a rapid heart beat, diarrhea, muscle twitches, or seizures, get help ASAP. You just re-started your prozac and are at risk for seratonin syndrome. You might give a call in to your doctor just to check that you're re-starting that medication correctly... plus you should get tamiflu if you're coming down with the flu, and it works best within 24 hours of symptoms, though i think the window is 48 hours.
Link: seratonin syndrome