Getting sick at night

Wondering if anyone else is experiencing this: .I am 39 weeks today, and for the past month, I have been waking up in the middle of the night with stomach pains, followed by a sour stomach, throwing up, and contractions. I went to l&d about it once, and they told me it was an irritated uterus due to dehydration and acid reflux. They told me to drink more, take my zantac, and stay elevated at night. Several weeks later I am still battling it. I'm losing sleep over it, and quite honestly am curious to see how much weight I've lost. I am literally getting up at like 3am and throwing up my dinner. Nothing is digesting. And forget drinking water, it comes right up. I've even tried to stop eating after 6 to allow the food to digest, and even then, I still get sick. The only difference is nothing but bile comes up. Im not going back to l&d just to have them send me home again..Does anyone else have this happen? And if so, have you found a way to fix the issue? My husband and I are sick of being up all night and something has to give. :(