It's very, very possible that its stress related. Don't give up though. You will eventually find the answer. Did you have your stomach checked out? I used to have anxiety attacks back in the day, and nausea was one of my symptoms. It was so horrible. I would not eat for 3 or 4 days, but still go to work and try to function. Are you going through a stressful situation? Keep trying to get answers from the doctors. Maybe if its stress related, they can put you on a low dose of an antidepressant. Does your family support you in this hard time you are having?

i did have my stomach looked at. i did multiple tests and everything came back normal. i have every day stress with school and such. but i think it's normal, and i shouldn't have so much stress that it's caused nausea for 2 years, ya know? it's ridiculous. but my family has been very supportive, but they are also at a loss for an explanation.