Don't worry, it's making you sick!
The only test for motion sickness you'll endure will be the stall/steep turn regime. If you can handle that you'll be fine.
Some students (cadets) do have a hard time with motion sickness. The good news is, over time, you'll build a tolerance against it and handle it better and better.
Some find ginger to settle their stomach. You may be able to buy ginger capsules. Try 1000-1500mg before you fly.
Or maybe just some ginger ale.
Good luck.