Hi. Thanks for your query. Noted the history and understood your concerns. I think sick means you are mentioning about vomiting as you have talked about sick contained lot of substance and was tasteless; you have had pizza with ketchup 2 hours before. This means the most probable cause is obviously ketchup as it is always red and not altered by the stomach juices. Since your family members are also have stomach bug, it is most probably due to stomach bug that you too have. I would advise you the following: Get the stool tested for occult blood the next time you have stools to confirm whether there was bleeding in upper GI tract. Upper GI Endoscopy if bleeding is suspected as this is the best way to prove or rule out. Clinical evaluation of all the family members including you to have proper diagnosis, investigations and proper management to have symptomatic and supportive treatment.