Ah you poor thing.
It does sound like a phobia of sorts.
No one likes the feeling of feeling sick, most people would rather be sick that feel sick iyswim!
Have you ever tried relaxation exercises? These can really help with "mild" fears (not saying you fear is mild and therefore not worth bothering with)
This is a good relaxation technique as to do it properly you need to concentrate on something other than feeling nauseous
Loosen your clothing, take off your shoes, and get comfortable. (Not relevent at the moment)
Take a few minutes to relax, breathing in and out in slow, deep breaths.
When you?re relaxed and ready to start, shift your attention to your right foot. Take a moment to focus on the way it feels.
Slowly tense the muscles in your right foot, squeezing as tightly as you can. Hold for a count of 10.
Relax your right foot. Focus on the tension flowing away and the way your foot feels as it becomes limp and loose.
Stay in this relaxed state for a moment, breathing deeply and slowly.
When you?re ready, shift your attention to your left foot. Follow the same sequence of muscle tension and release.
Move slowly up through your body, contracting and relaxing the muscle groups as you go.
It may take some practice at first, but try not to tense muscles other than those intended.
If you are left handed start with your left foot!
Would that help you think? if not there are lots of other relaxation techniques you just need to find one that works for you! Everyone is different there is NO right of wrong techniques, only what feels right to you! :-)