It is usually not recommended medicine at this age for cold and cough because of side effects. But the dosage given will not cause any major problem. It is advisable to give only nasal saline drops at this age for cough and cold.
Next Steps
this can occurs due to weather changes and temperature variations or simple cold and rarely infection.
kindly give nasal saline drops (nasoclear /nasivion s)every three hourly and since it is a salt water/saline water it does not have any side effects and can be given again and again for nasal blockage and respiratory cough.
it will dissolve mucus in nose and throat.
for fever and pain give paracetamol.
anti-cold medicines at this age have got side effects so can be given only after medical consultation.
try to prevent temperature variations around the child and you can also give indirect steam inhalation and if there is no improvement in 2 or 3 days then meet your doctor