eeewww...sorry about your being sick, that is not fun. As far as the carpet goes, yes, I think the baking soda can work well. What I have used before (dog barf!..don't ask...) is that stuff called "Awesome". You used to be able to get it at the dollar store. Works pretty good, and if you rinse really well, it doesn't come back up. My carpet cleaning guy said to always use plain water first, tho, because some soaps or detergents make it worse. I would do that, then use the Awesome.
As far as telling if you had food poisoning, it will usually hit you just like it did. And disapear when you have everything out of your system. (I got it twice) I only felt better after the only thing coming up was NOTHING. It lasted about 24 hours each time. Sometimes you get sick over and over until it is just gone. If it is really severe, check with a doctor, esp with kiddos. I had no fever or anything like that, just TERRIBLE stomache issues. But I also was told it depends on what you ingested. Mine was a reaction from something at a resturaunt they prepared. TWICE AT THE SAME PLACE! (uh no, I don't eat there any more...)
Long time ago...
Take care and hopefully you get that icky stain out!!:)
LT