H1B, H4 Visa

Eligible for drop box. Me and my wife we both are on H1b and working fulltime for very reputable firms for a long time and had no issues in the past going in person. Dropped of the documents on feb 21st 2018. Feb 23: got an email to attend for fingerprints and interview.(my wifes visa was approved though and she got her passport back by feb 24th). Interview date: March 19th. Initially we planned our trip only for two weeks.

March 19th: Attended the interview.
1. Took the email confirmation letter and Aadhar to the consulate.
2. Was directed to counter 6 to collect passport and then directed to counter 7 to give finger prints

Interview at counter 11
VO: Good morning
Me: Good morning

VO: Give me your I1797
Me: gave it

VO: Let me use my super power and guess. You are F1 to opt to h1b right?(she was already having a white slip in her hand)
Me: yes

VO: Have you ever been out of status
Me: No

VO: Employer name and salary
Me: YYYY

VO: State and city of workplace
Me: ZZZ

VO: Highest education
Me: MS

VO: There are no issues with your application, everything looks fine. But we need just couple of days for admin processing and handed me 221g with no documents required. She kept the passport with her and handed me 221g with the case number to track.

I am working fulltime from last 6 years and never had an issue.I am regretting dropping off the documents. She didnt give me any reason, just said its formal and just need couple of days.