I had stomach flu symptoms for 2 days and felt fine yesterday then they came back last night what should i do?

Stay hydrated: Make sure you're taking enough fluids, and eat only a bland diet until you feel completely better. This means easy to digest foods like rice, bananas, toast, plain baked potato, broth, etc. Avoid fried, heavy, fatty, saucy, creamy foods until your condition has returned to normal (and consider avoiding all that same stuff for your general health after you're better).

Go gently: Start with clear liquid like water, soda that is clear, or sports hydration drinks. Sip often to prevent dehydration. Work up to solids with bland foods like bananas, rice, applesauce, toast, gelatin, or chicken. Avoid alcohol, nicotine, caffeine, dairy & high fat foods. Rest.