From your history it is likely to be a viral infection. The thermometer shows normal then the temperature is normal and just recheck your steps and confirm that it is normal. Make the patient drink plenty of fluids(3 liters, have a liquid diet of soups and increase consistency as tolerated) and
vitamin C food items as it will help build immunity and will help in getting better. Avoid cold food and water and have hot water during this time. Do salt water gargling and steam inhalation thrice a day. You would require antihistamines to control the cold, an antipyretic which would control the fever and body pain.