Sounds like gastroenteritis to me. My motto is, if you are spontaneously puking with diarrhea and sweats, a virus is usually the culprit rather than an IBS "attack." My reasoning with this is that acute symptoms like these have a distinct origin, whereas IBS is this random label they give to people when nothing else can explain what's going on.
There's just a slight difference in treatment for a rotavirus (a common cause of the "stomach flu," which isn't really a flu at all, but that's the pet name for this "class" of buggers), at least coming from my school of thought: when you suspect viral gastroenteritis, you shouldn't take any Immodium or any other meds that paralyze your intestinal tract. The reasoning behind this is that the diarrhea that results from infection is a natural way for your body to expel it. However, some docs might order things like Immodium if you are becoming extremely dehydrated. Vomiting is usually treated sooner, with anti-emetics like Reglan, because you become dehydrated more quickly from vomiting than you would from D.
The best way to tell how dehydrated you are is by paying attention to your pee. If you've peed in the past few hours, you're generally not dangerously dehydrated and can treat yourself at home. If you haven't peed all day or it's dark yellow in color and you have a headache and dry mouth and dizziness, that's moderate dehydration and IV fluids may be warranted.
Are you feeling much better now?