I was a train wreck for about 3 days and then i couldn't have more than a few sips of water the first few days i was home. It's normal and you will be fine. You will literally grow into it, and learn how to chew food and not drink water at the same time like everyone else. Get ready for some big changes and weight loss. The fun has just started!
As for your blood clot question, it is normal. My best friend had it done before I did and he was puking clots of blood, which i never did after mine. He's fine, he went from 350 pounds to 174 pounds in 1 year. Hang in there.