You have a fear of being sick while flying that you feel sick ?
Ok challenge that perception by telling yourself that it's ok to be sick, not the end of the world and nothing bad will happen
Why not even try to make yourself sick
I had a friend 25 years ago and we flew a 172 to a grass field near Truro! He flew down and me back
He was a bit off colour when we went so took a sick back and sadly had to use it but it didn't bother him or his flying at all! He just apologised and got on with the job
So really it's your perception just get used to it ! It sounds like you have a fear of the process of being sick confront it which isn't to recoil but the opposite accept it as normal as breathing and take a sick bag as aircraft are hard to clean if you don't
Pace