So i have a bad cough the past couple of days and a bump showed up behind my ear it's small moveable and painless is it a lymph node? how do i get rid

Lymph node: It sounds like a lymph node. There is nothing you can do to get rid of it. Lymph nodes swell up as they filter out infection causing agents from the blood and help protect us. They usually shrink back down to an unnoticeable size after some time. However, sometimes, they do remain slightly swollen and hard due to scarring in the node.