Why do I feel sick? Please Help?

I have a severe phobia of vomit, and thus I do not like riding in cars (worried about motion sickness), cannot watch movies with vomit scenes, cannot read about vomit, and cannot listen to/ do anything that my brain has associated with vomit. (For example, I cannot listen to the song TiK ToK without getting nauseous because it reminds me of the glee episode where brittany threw up.) I also tend to get anxious easily and experience butterflies in my stomach which I mistake for stomach flu induced nausea, then I get panic attacks. I also don't have healthy eating habits. I often gag myself to make sure I'm not going to throw up, which sometimes makes my throat hurt. Roght now I'm super excited for graduation tomorrow and I'm getting nauseous and I ate a lot today and my stomach doesn't feel well and I hope I don't vomit. (I have vomited a total of 7 times in my life, and they were all before my phobia worsened.) Is there any way I can calm myself down or to tell if I'm going to vomit in the near future?