I am having mucus cough , cold , blocked nose and short breathness for one month. what can be the reason, i feel feverish but there is no temperature.

See below: It sounds as if you've come down with one of the many viral infections that have been going aroud. Keep yourself hydrated. If symptoms worsen, see your family doctor.

Post nasal drip: You have a post nasal drip.Get some saltwater nose drops and use at least four times a day. Turn on the hot shower and steam yourself at least twice a day and keep a vaporizer on at night get some mucin ex tablets and take one twice a day.