What jerks.

You are new at this. It is your first time. Of course you are going to fumble. Next time you can try to divert their behavior, try to act like it doesn't bother you, laugh along if you can, and say something like, yeah this is my first time doing this, I'm new. Do you mind showing me how you would do it?

Thats how you learn. No one is born knowing how to do anything. If you were hired and lasted 6 months, you are probobly quite competant in what you do.

if you really think you are better off alone, then the alternative is to just say, "Hey, I can't concentrate with you guys standing over me, please give me some space here."