What Causes Swelling On Ankle And Foot Covered In Bruises?

I injured my ankle (2) days ago. I think it is just a sprain but I am starting to worry that is may be more. My foot and ankle are both still very very swollen, and covered in bruises. The first night the pain was tremendous, but that has improved. Now it only hurts when I walk, if I touch it, or if I streach my foot at all (when i walk it must be flat footed or I cant support my weight). I thought I was on the mend, but today I am very sick to my stomach, and feeling very flushed. Could this be connected? Does this just sound like a sprain?