You need to take a deep breath and congratulate yourself for getting an interview. That is a HUGE accomplishment. The rule of thumb is if you get an interview, admission committee feels your "stats" are good enough to get in, and they want to meet you and evaluate you on a personal level. Could you still get rejected after your interview bc ppl have better stats (or you bomb the interview), the answer is yes, especially if it's a smaller school whose class is almost full. But you have an opportunity to let your personality and desire for medicine over shadow any "red flags" you may or may not have. Remember that.
The best advice I can give you is not worry about other ppl's stats, and just focus on preparing for the interview. Look up questions that each school has a tendency to ask and practice your answers. You do that all this and you'll get in! If you only focus on what others bring to the table and not yourself, then you are handicapping yourself to succeed at what will be your best opportunity to shine as an applicant. In conclusion, hit a home run at the interview and you'll be fine!
If you don't mind me asking, where are you interviewing at?