How Long Does It Take To Heal Injury Of Leg?

I fell from the roof of a 1 and a half story building while putting up christmas lights. I landed on one foot and it caused extreme pain on the bottom of my foot. As I was getting up and started walking, I began to feel light headed, lost vision, and could not hear well. I assumed I was going to faint, so I bent down with my head between my feet and I regained consciousness. My foot is now swollen and slightly dark.How long do these types of injuries take to recover?What should I be doing to aid in the process of healing?What could have caused me to almost faint?