Hi, I Had A Fall Couple Of Hours Ago And

Hi, I had a fall couple of hours ago and bang my left side rib case on the metal steps. Took me a few seconds to get up and I could not talk then because of the pain. It is still hurts now under my left breast on the side and front. It hurts when I breath and I can not take a deep breath. There is no visible mark or bruise that I can see. What should I do? Do I need to worry about internal bleeding or how do I know if any organ was damaged? I very much appreciate your answer and many thanks in advance.