Help me understand pls; why commonly do i suffer from coughing, mucus and blocked nose after having a day or two of sore throat symptoms, not during?

Spread of infection: What you described suggests viral infection and virus may affect different tissues at different times in the course of an infection. For example measles causes sore throat before there is skin rash. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Drink enough water daily so that your urine is mostly colorless. Practice safe sex.