well, having suffered through many of my early FAMS as i did due to the wonderful effects of air sickness, i can give you some good gouge.
I don't get sick on rollercoasters, in cars, or on passenger planes. I get sick on the open ocean and used to when i flew. You may not get sick on a regular plane, but the T-34 is a unique beast. However, even if you do, they will work with you.
After the first three or so flights, if you're still getting sick they will give you some meds that work, at least in my case, really well. You must be off the meds by your first checkride though, as you must be able to fly your solo without the aid of meds. I managed to get through my checkride without meds (but we had to fly straight and level for a bit after we did spins) and i was careful on my solo - flying and puking up my toenails at the same time seemed like poor headwork. If your sickness is really bad and you either don't respond to the meds or you can't be weaned off of them, you'll be sent to the "Spin and Puke".
Spin and puke (i didn't have to do it, but i was damn close) is just like it sounds. YOu sit in a chair with your head on a tray in front of you (like a tray table on a plane, built into the chair) and your spun. You aren't spun very fast, but then they ask you to sit up quickly, inducing HUGE vertigo. Just seeing the chair made me ill. Anyhow, they'll hit you with the chair for a few sessions each day for a few days or weeks until either your body gets used to it, you need further "treatment" or you DOR.
If you are sent to further "treatment" you go to Pensacola to get sent to the bigger spin and puke. I didn't see this happy fun place, but i understand it was the regular chair on steroids. ALso, this goes on for MONTHS. I met an ensign (NFO i think) who was going to this treatment, he said it was all he could do to go in ever day..for HOURS of pure hell. Apparently it did work for him.
I understand that the Air Force is a bit more aggressive (draconian) in their treatment in that if you puke on your first ride or two, you get the treatment (the nasty one too). I can't confirm much about that though.
You CAN make it through. I know of several people who gave up. It does suck, hard. It makes flying so much harder and studying near impossible. You'll go home and you'll just want curl up and die, but you know you can't. I'd say most people make it, really they'll give you many chances to get help for it, they will work with you as long as you keep showing up with PMA (positive mental attitude).
I wouldn't worry about it if i were you. If you get it, you'll most likely get over it in a flight or two, if not, suck it up. Becoming a naval aviator is worth it, best damn day of my life.