Ok lady's I been supper nausea, and getting sick on and off since the 20th. I also been have…

Ok lady's I been supper nausea, and getting sick on and off since the 20th. I also been have sensitivity to smells. Lite cramping not in my overly area like normal in the middle. I went to the hospital Monday because I had not held any food or drinks down for over 12 hours. They did a pee pregnancy test it was negative. They refused to do a blood. But all this keeps going on. My period is due the 31st. My husband wants me to get a test today and take it tomorrow morning. Is there any use in that or should I just want until the 31st.