I'm 19 weeks pregnant and it seems I may have a stomach bug or something. For the last 5 hours I've been throwing up every 30 minutes. I'm drinking ginger ale to try to keep something down but most seems to come back up. I tried calling my doctor but their office is closed for the weekend. When should I start be worried and go to the hospital? I don't have a fever or anything besides throwing up. Is their anything I can do to stop it?