How Can Pain In The Feet Due To An Injury Be Treated?

About two weeks ago, I was walking down a flight of stairs and missed the last stair and landed hard on my right foot. I have had pain in my arch that has never gone away - when I rest and then get up the outside of my foot is painful and I walk with a bit of a limp. Most recently it has gotten a bite worse but not to the point that I cannot walk. No swelling and I can press on the arch of my foot without pain - outside is some minor pain when I press it.