Hi Megan and welcome to the site...I'm sorry you've been feeling so sick. Bear with me now, because I tend to ask a lot of questions. Your doctor should also be asking you a lot of questions; just something to keep in mind :) When someone goes to the doc complaining of nausea, vomiting, diarrhea, etc. the diagnosis of a GI (gastrointestinal) virus is pretty common, because that's what most of these symptoms usually point to. But when it lasts for two months, you're no longer dealing with a run-of-the-mill GI virus.
The first thing you should do is make another appointment with your primary care physician. In the meantime, you should begin organizing yourself so you can give him all of the info he needs to know.
Here are some questions that your doc should be asking:
1) What are the specific symptoms you have?
2) When did the symptoms start?
3) Do you have pain, and if so, where is it located?
4) When you notice these symptoms, how long do they last (i.e., do you only notice that they last for a couple hours after you eat, or only in the afternoons, etc.)?
5) How would you characterize the sensation of your pain (i.e., achey, burning, throbbing, also how severe on a scale from 1-10, etc.)?
6) Does anything seem to make it worse (i.e., particular foods, situations, etc.)?
7) Does anything seem to make it better (i.e., any over-the-counter medications, foods, etc.)?
Your doctor might refer you to a gastroenterologist, who specializes in GI disorders. This would probably be a good idea, based on the fact that you are vomiting every day and having that much diarrhea. IBS is a diagnosis of exclusion, which means they have to rule out other causes of your symptoms before you get such a diagnosis. There are so many things that can cause these symptoms and it is your doctor's job to work it up for you; that's what they went to 2333974 years of school for.
Disorders of the gallbladder, liver, pancreas, stomach, small and large intestine, etc. can cause these sorts of issues and so no one will be able to really help you with a "diagnosis," but people will share their experiences and hopefully be able to help you feel a little less alone in all this. Again, welcome.