Please help me!!?

It could be anything from a bowel obstruction, to a bad reaction to the food- honestly, it could be just about anything but from what you are saying, It sounds like he may have swallowed something? I know they can vomit AND have diareha when they have something "stuck"- an obstruction. Call a local vet, if you can- most cities have 24 hour emergency vets and they will at least answer your questions for you. Better to be safe than sorry. I really hope he's ok.