Hey, i ve recently had a very bad flu . A week before that my throat was infected. My flu mostly went away but now im having back/ kidney pain. İt starts from the tip of my rib and aches towards my kidney. Today i was coughing and i felt that something inside popped and the pain got much worse. I took some painkillers which lessened the pain but i was wondering if i should see a octor or is it just dehydration after a flu?