Oh yeah, chucked up like a champion during my training. Once on a PPL nav, hot bouncy day, high work load. Up came lunch. Missed the map I might add
When I first did stalls I got green but kept breaky where it does me the most good.
During spin training for my instructor rating I wasn't the best either. Rotten instructor laughed at me. I later found out he was 1 spin away from joining me.
Things settled down for ages. Then, I hadn't been flying for a long time. Hot day (Kimberley, WA) and lots of thermals. I was paxing to get a feel for the area. Up came lunch again.
After that, I haven't been crook since.
I am a lousy pax in a bugsmasher though, need to have lots of airflow around me.
4500 hours later in mainly smallish (ie less than 36 seats) I haven't been crook again. (That wasn't self inflicted)
It does pass. Keep as cool as possible, lots of fresh air, no tight clothing, nothing too "interesting" to eat. Don't be hungover!! Avoid rich foods and foods high in acid content. Also, be as prepared as possible so you aren't nervous or worried about your flight.
Regarding temperature, to keep your instructor happy and to keep in thinking with CPL ops, ask your instructor if he/she's hot or cold. It'll show that you're thinking of the pax and not just yourself.