When the body is suffering from infection like a sore throat or earache, the antibodies are produced by the body to fight the bacteria and virus causing the infection. The dead microorganisms accumulate in the lymph nodes, making them swell and tender to touch.  The swelling will usually subside in one or two days for a minor infection. In case the infection is severe, the swelling will be more pronounced and painful.  In some leakages there may some leakage of the lymphatic fluid.

In case the swelling does not subside even after a few weeks, it is advisable to contact a doctor  who will provide medication to treat the problem. Usually the swelling subsides after some time, but the skin  may be discoloured.