What Causes Nausea And Vomiting Along With Weakness?

I have been nauseous for a week, with some vomiting although that has stopped;I am fatigued during the day and everything smells bad to me (not unlike an early pregnancy).I am an otherwise healthy 55 y/o female, 5 2 ,130 lbs.I feel like I m feeling incrementally better each day; however, why does everything smell fowl?