after the interview, be sure to send a thank-you note - it's a nice touch, and shows that you're interested in the opportunity. Don't overthink it - just be sincere, and express your gratitude for the chance to interview. With a little practice, and a lot of confidence, you'll be acing residency interviews in no time.
In conclusion, the "Tell me about yourself" question is not as scary as it seems. With a little preparation, and a lot of personality, you can nail it and make a lasting impression on your interviewers. So go out there, be yourself, and show them what you're made of - you got this.
Oh, and one more thing - don't forget to breathe. It's easy to get caught up in the moment, but stay calm, stay focused, and you'll do just fine. Good luck, and happy interviewing.