I would definitely get to the ER to see if there is something they can do to help. Vomiting excessively for 12 hours staright cannot be good and eventually you will become so weak, dizzy and it will not be good for baby. When you are preg, there is not shame in going to ER if you think there is even a slight possibility of illness. Hope you feel better soon.
AND PLEASE FEEL BETTER SOON!!!
If it is that bad - call your dr they may be able to call you in a suppository to hold off the vomiting.. if not they may want you to come in.. but you should call.