What Causes Severe Pain In The Flank While Coughing?

I have had a bad cough (getting over the flu) and today I was coughing really hard when I got an intense pain in my kidney area. Hours later, it still hurts so I am hoping it was a muscle that got tweaked. However, I have polycystic kidney disease and I am afraid one of the cysts might have ruptured. Is that possible?