Daughter vomited what she describes as "tomato" red liquid. She said it did not have any taste of metal and only threw up once.?

Blood??? did she drink or eat anything that will stain the food with red color. As long as it is not blood, she can rest her stomach by eating soups, and stay on liquid diet, nothing red. Drink ginger ale, or seven up, eat saltine cracker. If happen again go to the emergency room.