Definitely go to the ER. I've heard of girls having this happen and being fine, but it is always better to make sure with this. Coughing up blood can be a sign of a blood clot in the lung or something serious like that. Tell them everything. Stay calm and good luck!
Pregnant or not pregnant coughing/throwing up blood isn't normal. You should call your doctor. Hope you find out what it is
Call the doctor or go to the er!!