Hello. It may be due to throat infection in recent days. Causing swelling of regional lymph nodes. If that s the case then it will resolve in a few days with antibiotics. But sometimes it may be enlargement if parotid gland ( which secrete saliva in mouth) which will present with pain and numbness and sometimes increased saliva in mouth. In this case you have to visit an ear ,nose and thraot specialist who can run some investigations to reach a diagnosis like fine needle aspiration or neck ultrasound. Hope that answer the question. Thanks