I have a Bernina 430 and I found it very intuitive to use, just jumped right in (but not the embroidery- I had no clue what to do...) The threading worked like my two previous machines (but I didn't use the threader) and I had a vertical bobbin in my very first machine, so I knew how that worked.
However, when I went to the dealer for my first class, I noticed many of the women had never even turned their machine on. What you are feeling is not unique, many people are overwhelmed by these electronic machines. Just wait until your class, and then I'm sure you'll figure it out. No need to be overwhelmed, just keep taking classes and learn a little more each time.