Visitor Visa - B2

I have an interview at Islamabad Embassy in 17th of Mach 2016. I have a fresh passport with indicating no visa yet. I was sure that he will reject me because I have no travel history. Be honestly I have studied the immihelp site frequently. My interview time was 10:30 am.
I have passed my passport on window to VO and
Me: good morning Sir
VO: Good Morning
VO: what’s your purpose of visit?
Me: to meet my bother and for Tourism
VO: Brother! Where your brother living?
Me: xxxxx, Mo
VO: Sorry?
Me: answer again
VO: what’s he do?
Me: answered
VO: How he move to United States?
Me: answered
VO: How long he is in United States?
Me: almost two year
VO: when will he move to United States?
Me: Answered
VO: you have mentioned in your application that you run your own business is it your business?
Me: yes Sir
VO: Are you sure?
Me: Yes Sir
VO: what kind of business you have?
Me: Answered
VO: How many Employee you have?
Me: Answered
VO: How long would you stay?
Me: 20 Days almost 3 weeks
VO: have you traveled any other country?
Me: I did understand his question, he asked me thrice I say Sorry? At 4th time I answered No Sir
VO: are you married?
Me: Yes Sir
VO: how many kids you have?
Me: I have two kids but one of my kid is passed away?
VO: Oh Sorry
Me: it’s ok Sir
VO: what’s your wife do?
Me: she is a housewife
VO: what’s your father do?
Me: He is a manger in a local factory
VO: where he live?
Me: He is living with us at Pakistan

After that he said that Congratulations your visa is approved. Collect your passport within two or three working days.
 Me: Thank you very much sir

Note: the following should note while going for an Interview
1. Well prepared
2. Well-dressed coz American like it
3. Don’t be over smart
4. Tell him truth
5. Answer to the point
6. Be confident

and Good luck for those who wants to apply for USA