When I was in the EDU, it was often talked about that we 'store' our emotions in our tummy, wich can often make us feel full, when physically we are not.
Even if you just ate toast for the time being, just to get your energy levels up, that may help ease the nausea, help you think more clearly and even lift your mood a little. It's not going to be a miracle cure, obviously, but even if it helps a little, that is good.
With the energy drinks, avoid the major caffienated ones like RedBull etc and go for the more glucose isotonic based ones like Lucozade, which help to restore a more natural balance of hydration. Also, are you drinking enough water? You may be dehydrated too, often if we neglect to eat, drinking fluids also gets forgotton. Dehyration plays havoc with physical health.
I know all this is easier said than done but please try hunny.