I don't know if this helps but I am 34 weeks and I have had 'the runs' so to speak for at least the last 2 weeks and also i have been vommitting on and off aswell. I don't have a virus or anything but I asked my OB and he doesn't seemed concerned. I think this is just another 'joy' of pregnancy in the last trimester. I have to say I am not enjoying this last trimester at all!! I can hardly walk on top of everything else that is going on. I hope it helps knowing that someone else is going through something similar.