Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern.... As per your complain a swelling under the jaw can be swollen lymph nodes which can be due to some infection origination from teeth or other infections in head and neck structures and pain from the glands may radiate from jaw to ear.. -Other reason can be inflammation of gum flap over the wisdom tooth known as PERICORONITIS and the inflammation leads to severe pain and swollen lymph nodes and pain can radiate to jaw and ear.. -Another reason can be infection or clogged duct of Submandibular salivary gland which is also located just below the jaw line and any infection or clogged duct of the gland due to some foreign body or formation of crystalline stones from minerals in saliva can lead to swelling and pain.. You need to consult an Oral physician and get evaluated and get treated according to diagnosis.. In case of pain and swelling due to tooth infection antibiotics, painkillers and treatment of offending tooth can relieve.. In case of Pericoronits antibiotics, painkillers along with warm saline gargles and either removal of offending gum flap or extraction of wisdom tooth in case if it is impacted has to be done.. In case of infection in salivary gland antibiotics, painkillers will help while for clogged duct removal of the obstructing stones is the treatment of choice.. As of now you can take OTC painkiller like Ibuprofen [Advil or Motrin] for relief from pain and visit an oral physician without any delay to resolve the discomfort.. Hope this information helps.. If you find the answer helpful please give me a Five Star Review and click on found the answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..