Cristina,
To relieve nausea and vomiting, you need to take crackers. Eat small servings frequently like every 2-3 hours. Eat foods that are not fatty and spicy.
If you vomit quite a lot, you have to see your Obstetrician because you might get dehydrated and may need some intravenous fluids.
Take care and I sure hope you'll feel better.