Whats wrong with me

I found out I was pregnant, my period is 15 days late, well, yesterday, I threw up after I woke up. I threw up again, a little bit before bed. I haven't ate anything in 3 days but a couple of crackers and drunk a little to keep from puking again. Today, at 5 am, I threw up again, and I've been puking all day, I can't keep anything down, im so thirsty. Is it a virus? Or the baby