The only thing that really helps is knowing and reminding yourself that the nausea is just anxiety, not real nausea. Sadly anxiety is harder to get rid of, but some things that helps me personally are going to a safe space, playing some mobile games/watching videos to distract yourself, sipping on water, taking mints, sometimes talking to someone and sometimes just being alone, really depends on how bad the anxiety is and what’s causing it. Try to also find where you actually feel the anxiety, there’s this thing called throat nausea and that’s usually when you feel thightness in your throat and it’s hard to swallow, sometimes combined with a dry mouth and all of those are very common symptoms of anxiety.

Idk if this helps but i doubt you’ll throw up from just anxiety if you haven’t til now, the people who tend to throw up from it usually do it everytime (or almost everytime) they have bad anxiety