What Causes Popping Of Lower Limbs Leading To Sharp Pain While Sneezing?

I sneezed a couple of days ago, heard a pop to my left lateral lower ribs. Felt immediate, sharp pain. Day after it was terribly sore, now the pain has increased so much that I can hardly move my left arm, take a deep breath or turn d/t this sharp, intense pain. I dont want to rush to my PMD or ED if not necessary. Any thoughts?