 [ Symptoms ] can you have a baby with someone and the baby look like someone else [ Disease ] you are right to be concerned what may have started out as an allergy or even a cold may have turned into something more serious coughing up mucous can be caused by the post nasal drip of allergies or sinus infection but it can also be from a cold asthma bronchitis or even pneumonia the only way to know is for your doctor to take a look and listen your symptoms have been going on long enough that you should give your doctor a call you need to find out what is going on and how to get some relief here is a great webmd article on cough that can give you more information hope you feel better soon