33 weeks and 3 days. Got SO sick last night.

I was waking up coughing because the heartburn was so awful and I'd throw up. I did this from about midnight to almost 5 am. Is it normal to throw up that often? I also am haveing some lower back pain. So my questions are should I stay home from work today? And should I be concerned that I got so sick so often all at once? I called my doctor and I'm waiting to hear back. Hoping she doesn't want to admit me so they can get fluids in me. I have decent insurance but I'm sure it'll still cost a lot.