Diarrhoea continues for a week

having diarrhea can mean a lot of things. One reason could just be stress, another is food poisoning. You could even have a parasitic bowel infection, depending on how bad the diarrhea is. You could also be constipated or have some sort of digestive disorder causing it. YOu should go check with your doctor to diagnose the problem, and then fix it. The list goes on and on about why you have diarrhea, so i would seek a doctor.