No one better than you and the interviewer can tell if you did well in your interview. People here will be very little effective in reassuring you.
Quote:
My essays and recommendations are strong.
I love this sentence. It kind of says:"Don't worry, my essays and recommendations are strong. Please focus on my question because I nailed the rest of my application."
We have no idea what makes one essay or recommendation strong, but still a lot of people write this as if there were no doubt their application is great based on (?). Being rejected by HBS and accepted everywhere else doesn't mean a poor essay. The other way around is also true.
To answer your question, don't worry about having bombwed the interview, we're sure you did great. And wait for your interview result before jumping into conclusions. Best of luck!