thank you for your query.... well the causes for swollen lymph nodes in neck are quite a few... most commonly they can be due to bacterial infections leading to ear nose and throat problems...also tuberculosis, lymphoma or leukemia may present with swollen lymph nodes....but most commonly infections are suspected... swollen lymph nodes in neck for a month mostly points towards some chronic infection.... as for the pain during inhalation, there might be some reasons as well...it could be because of some external injury or some strain most commonly, when the pain will be more superficial....but some lung pathologies might be the cause, here the pain will be deep-seated... a chest xray might be useful in this condition, also a course of antibiotics can work for the enlarged nodes...failure of which will need blood reports and maybe even lymph node biopsy later... hope this was useful....