What should i do if i havent been able to hold anything down for almost a week now, have these constant dull stabbing pains in my abdomen that get worse throughout the day, nausea, diarrhea and fatigue?

You must be examined&tested in the ER at this time. Dehydration & electrolyte imbalance are quite likely not to mention possible kidney failure. Nausea,vomiting&diarrhea are most often caused by viral gastroenteritis or food poisoning, but after a week,stool cultures are a must. Careful exam of your abdomen is needed to check for other more serious causes of abdominal pains.