Re: Could this harm my baby?
Since your immune system is weakened right now, I would definatly suggest calling your doctor and asking what medications are safe for you to take. I had a simple cold that took me 3 weeks to get over; I dont even want to imagine what the stomach flu would do.
As Bxr said, keep hydrated, make sure to eat, and get plently of rest. It shouldnt harm the baby as long as you take care of yourself.
Hope you feel better!