 [ Symptoms ] how can i know if my coldflu has become bacterial so i can take a ampicillin  i am aware that ampicillin does nothing if my coldflu is a virus but i have been sick for a week now and although my body is not soreweak anymore i still cough up alot of mucus and coughing hurts my chest a bit and i have a sore throat also runny nose with alot of mucus as well [ Disease ] cold and flu are viral infections colds tend to run their course in 7   10 days but it can take a little longer flu generally is at its worst for the first 3 or 4 days but can take up to two weeks to ease up completely please click into the linked information and read about it if more than 10 days go by and you still see no relief or your symptoms are getting worse then you should call your doctor he or she may want to see you in their office again or try another form of treatment if you are considering taking antibiotics that were prescribed for something else please do not do that without consulting your doctor we hope you feel better soon the webmd answers staff