Hi, I really appreciate your concern. If this was the viral infection then such symptoms was likely that includes the diarrhea, vomiting and ultimately it might have caused the electrolyte imbalance and so you are feeling weakness, it is better to rehydrate with oral rehydration therapy you can even prepared the rehydration drink at home, with Glucose powder, pinch of salt and little lemon juice, else it is nothing to worry. Hope this information helps. Let me know if I can assist you further. Regards, Dr. Akhtarhusain Shaikh