What Causes Sharp Pain In The Mid Of Rib Cage While Coughing And Sneezing?

I was doing some leg presses at the Gym and went all the way down with a considerable amount of weight. After a few reps I heard a "pop" and felt a sharp pain in my right side around the middle of my rib cage. It has been extremely tender for a couple of days. It hurt when I coughed or sneezed at first but is somewhat better.