It could also be your sinues dripping into your throat and chest. Do you have any other symptoms such as fever, pain, shortness of breath, coughing? If you have those, then I would see your doctor, but if not and you feel OK, maybe just take a decongestant and see if that helps.
The clicking sounds is known as rales or a crakling sound. It can be due to bronchitis, pneunomia, pulmonary fibrosis, left sided congestive heart failure, pulmonary edema, and other things. It is best to get checked. Have you had a virus lately such as the flu or a bad cold? Some times you can get walking pneumonia after that or bronchitis.