Well first off, breathe. Second off, was she not feeling well before you guys went out to dinner? If so, you can have a little exposure just because she was probably already having symptoms but not showing them. If she was feeling fine before dinner and then when you guys got home and puked, it could of been something she ate that did not agree with her stomach or food poisoning. There could be a number of things. But if she did not puke right in front or on you, then you should be fine just wash your hands and if you are really nervous, don't go over their house for the next few days just in case.