Since your symptoms are mild and have lasted six days, it is likely a common viral infection, which usually resolves within a week or two. For relief, you can take paracetamol or ibuprofen to help with the mild fever and headache. For the cold, steam inhalation, warm fluids, and saline nasal drops can ease congestion. Be sure to get plenty of rest and stay well-hydrated. Since you have been unwell for six days, if your symptoms worsen, or if you develop a high fever or difficulty breathing, please consult a doctor in person for a proper checkup. Rest up and take care!