H1B, H4 Visa

I have attended the H1B interview on 22-11-2017 at Hyderabad consulate. Here is my experience:

VO asked my passport and I-797A. She scanned the passport, stopped and looked over my passport again and then rushed into a room. I don't know what went there. She came back after 5-7 mins and asked me the following questions:

VO: How long have you been working at ZZZ?
Me: Answered

VO: When did you graduate?
Me: Answered

VO: What was your major?
Me: Answered

VO: Did you work on OPT prior to your H1B approval?
Me: Answered

VO: Did you OPT expire before your H1B?
Me: At first I said No, but then I said yes, it was valid until xxx and then I had an extension.

VO: Ok..ok. What is your designation?
Me: Answered

VO: What is your salary?
Me: Answered

VO: I am sorry, what was that again?
Me: Answered

VO: Are you married?
Me: No

VO picks up a white paper (221g) and hands it over to me along with my passport and I-797A and said you'll get an email from consulate for further verification. We cannot verify your case as yet. You will get instructions in the email. You can check the status of your case. Your case number is on the 221(g).

I read at many places it could be because of a common muslim name (I am Mohammed Hameed Hussain), not sure though. I have had to wait for secondary inspections at the port of entry the last two times I entered US. How long does it take for the case to get processed?