i'm a private pilot and i agree.
tell the instructor up front your concerns, and you're not interested
in long term plans so they know it's just for a couple classes, and
since you're a nervous flyer will understand that from beginning. tell
the instructor EXACTLY what you posted - you're not freaked out by
flying, but want to understand it more.
sensations are more noticible and direct in a light aircraft, and YOU
will be doing some light turns, banks, climbs and descents. so YOU
will know why and how a plane is doing something.
also GA flights are arond 1,000-5,000 feet around a city, you'l LOVE
seeing sights in your hometown from this level, and probably won't want
to land.
a warning to your wallet: you may like it and want to proceed further
oh and of course schedule in the morning -- 7a - 11am. air is much
calmer.
might want to visit rec.aviation.student and post this with your city,
may get some recommendations.
all the best