My (about 21 month) puppy fel of deck and is puking?

Yesterday my 21 month-old puppy fell off the deck when he was walking up the steps. My deck I'd about 12 feet high. Now he is throwing up a light greenish foamy puke, an he has slept most the day. What is wrong with him? What should I do? I'm already taking him to the vet tomorrow. Please respond ASAP!!