Some people will become shocked when they see that the lever is not available. There is nothing to worry about.You simply need to turn the handwheel and you can watch the handwheel appear. There is no need for you to call the teacher. Panicking will not do you any good for sure.
Sewing requires skill that may be easy for some people but there are also some who feel that this is a skill that can be used quite well especially in some emergency situations wherein you need to sew a few things. You should know how to use the machine in order to sew fast. Who knows, you might make more items that way.