Had 3 vomiting feels like too much saliva today. Can that be stomach flu starting or something worse?

Depends on severity. If you allow you stomach to rest: nothing by mouth for a few hours-it will allow the peristalsis waves to re-boot forward not backward. Offer small sips: sports drink, soups, and later starches. If diarrhea follows-may be a viral stomach bug. Fever, no desire to eat or drink or not tolerating after stomach rest along with severe stomach ache or bloody/mucousy bm is time for the ED visit.