Hope and Faith, I highly recommend going to see a trainer! Of course they won't laugh at you.. they're there to help and to motivate! Really, it helps sooo much to know how to use all of the equipment even if you don't think you're going to use it all. You might want to in the future, as you increase your stamina/strength it's always nice to change things up for a little variety.
Point is, everyone has to start somewhere, and kudos to you for signing up for that spinning class! If you're into group exercise, you should check out pilates or yoga as well.