There is no need to fear anything in the interview if you are:
From a good, recognized institution; Have strong financial support; Have high scores in entrance exams (GRE, GMAT, TOEFL); Admission to a recognized University not some small-time (community) college; Able to speak confidently and clearly about yourself and your career goals;
Even you are lacking in one or all of the above, you can do well in the interview if you can give plausible explanations for your shortcomings.
The interview mostly lasts about 3 - 5 minutes. It is nothing like a job interview.
All the consulate official wants to know is that you are capable of succeeding and that you won't become a nuisance or deprive some worthy student of an opportunity because you got ahead of that student and ruined it for all after you (Like students from Andhra Pradesh do)!!
