Business Visa - B1

My Bio-metric was on 17th Feb 2015 and Interview date 23rd Feb 2015.
I went to Mumbai consulate on 23 Feb 2015 at 9:00 am. The VO was very polite and of middle age.
My interview:

Me: Good Morning Sir
VO: Good Morning, Your passport please,
VO: Where r u going?
ME: Philadelphia,
VO: For what pupose??
Me: To present a paper at International Conference.
VO: Did you visited any country before
Me: Yes sir, I visited malaysia in Nov 2012.
VO: Was the visit for presenting paper?
Me: Yes Sir.
VO: Explain your project?
Me: I just explained the title of paper.
VO: Explain in detailed about anticancer project.
Me: I explained
VO: What do you do?
Me: I am working as Assist. Professor at AAA institute of BBB
VO: Who is going to pay for your trip.
Me; I got travel grant from CCC Indian govt. organization.
VO: What is your highest qualification?
Me: M. Pharmacy.
VO: Did u submitted dissertation or Thesis?
Me: Yes Sir,
VO: Explain your M. Pharmacy topic.
Me: Explained in detail about Anti HIV project
VO: Ok. Then he continued typing on his PC for near about 2 min. Then asked when you are planning to go?
Me: 11th April and Tenure 1 week.
VO: Again continued to type on his PC for near about 2 min. He pick up one slip from his cupboard and Then said we need to investigate your case in detail and for this you need to send an e mail containing documents mentioned in slip. The final decision will be based on that investigation. Till then your visa will be pending as per 221 (g)
Me: By looking at slip, Sir, I have these documents with me now.
VO: You need to send email.
Me; Ok sir. Thank you. and left window.

As per the instruction from respected consular, I have sent an e mail on 24th Feb 2015. I have not received any confirmation regarding receipt of email.
My conference is on 13th April. I have already registered for conference. I am too much tense that whether my visa will be approved before my conference or not.