One day of fever with body weakness and a sour taste in the mouth is usually a viral fever with some acidity/gastritis riding along - very common this season. Paracetamol 650 mg every 6-8 hours when the temperature is up, 3 litres of fluids, and light food; skip antibiotics on day one. At 48 the thing to watch is duration: if fever crosses day 3 or is spiking with chills, get CBC,
CRP, dengue NS1 and malaria smear done. Same-day check-up if you get breathlessness, chest pain, drowsiness, or your urine output drops.
Next Steps
Track your temperature 4 times a day for 48 hours. If it is not settling by day 3, book me on Practo with the fever chart and we will pick the right tests instead of guessing.