Many students are overly worried about the examiner. They worry about body language, eye contact, how friendly the examiner is, whether the examiner smiles, whether he/she is making notes, what his/her opinion might be etc.
This kind of worrying is a waste of time and energy. My advice is that you should only worry about 2 things in the speaking test: 1) listening carefully to the questions 2) trying your best to give good answers. Its a language exam, so lets worry about language.