I agree with what everyone has posted.
Don't be too hard on yourself, expecting perfection right off the bat.
Have fun.

make sure to take bobbins, thread, a foot pedal, and your power cord, oh and your foot. I ha.e forgot bobbins, luckily they sold prewound, have seen others forget cords and such and they live far. You'd be surprised how easy it is to forget the simple thing. Label your stuff. It all starts to look alike after a while. Make sure not to forget your mat and rotary cutter. The most important is to have fun and get the most you can out of the class. Don't be afraid to ask questions even from your classmates. Sometimes you can learn new things from them as well.

Just relax and enjoy it.

When I went to my first lesson, for my first quilt, I wish I had concentrated LESS intensely on my quilt and gotten to know the other quiters better. The teacher labeled me the "overachiever" because I was sooo intense and finished my quilt so quickly (there were two parts of this class, a week apart).

Also, I was astonished that my carefully chosen colors/patterned fabrics weren't so great next to each other and was very glad that I followed the suggestion NOT to cut out all the fabric before hand. I still cut out fabric only when I get to the place it is needed. Of course if I am doing something repetitious I cut them all out, but I double check how the first looks before I cut the rests!