I'm not an expert but from the looks of it, it seems, the officer wants to verify your
work experience/employment history, as, generally speaking, a medical practitioner with 5 years work experience is expected to have enough funds/savings.
Maybe, the processing officer got a little curious about the gift deed from your parents and s/he thought it would be better to call you in for an interview, and examine your employment history, bank statements and pay stubs to make sure your claimed work experience is true and that you actually possess the funds required.
Just provide the requested documents, and if possible, take the pay stubs for the entire (5 years) employment term (or at least, the first few and the last ones), any work contract(s)/joining letter(s), etc., and if you can, the old bank statements showing your salary deposits.
During the interview, try to relax and act natural. Officers are friendly and helpful. Nothing to worry.
Here's a link to a recent interview experience as described by an EE applicant:
Good luck!