Foot/ankle sprained/fractured/broken?

hey everyone! so earlier today i was in the city and i ended up falling down some stairs... i landed on my left foot and hit the left side (outer part) really hard against the concrete. at first i just walked it off and tried not to think about the pain, but once i got home around 8:00, my foot was KILLING ME. its swollen on the left side and the top of my foot and i have some bruising on the inner, top, and outer portions of my foot. the swelling is not TERRIBLE, but the pain is. so my question, do you think i sprained/fractured/or broke my foot? please help! p.s. the pain is also spreading to the inner part of my left foot, and i have been icing it and keeping it elevated!