To God be all the glory. I want to specially appreciate Texrem, I only sent him a pm to help me pay my sevis fee and he followed me up since then. For the advice, encouragement, support, mock interviews, I am grateful. God bless you.
So, I went for my first interview on Tuesday, June 20. I was the fifth to be interviewed by the guy and all four before me were denied. Here's the transcript:

Vo: pass me your passport and I20
Me: here they are
Vo: I see you are going to west chester university
Me: yes
Vo: what course will you be going for?
Me: masters in public health
Vo: okay, how many schools did you apply to?
Me: 3
Vo: list them
Me: university of Maryland, Pennsylvania State uni and west chester university
Vo: so, why not Penn State
Me: west chester was actually recommended to me by a senior colleague at work who graduated from the school and the tuition is affordable...cuts in
VO: what do you do currently?
Me: I am the superintendent pharmacist at xxxxx Pharmacy in ilorin
Vo: okay, who will pay your tuition?
Me: my dad and my uncle
Vo: what do they do
Me: my dad is a permanent secretary while my uncle is a civil engineer, he has his firm in ilorin and abuja here.
Vo: I'm sorry I can't approve your visa now, the reasons are stated in this letter.....next applicant window 6....
I was weak.
Two days after, I paid another visa fee and booked July6 Lagos consulate. I just kept praying to God. I read all transcripts on the thread, both delayed and approved and I practiced consistently.
Fast forward to July6
Vo : good morning madam, how are you?
Me: I'm fine, how are you too?
Vo: I'm fine, thank you (sips coffee), pass me your documents
Me: here( I passed my passport and i20)
Vo: tell me about your school
Me: West Chester University is a public school in Pennsylvania State (vo cuts in)
Vo: how did you hear about the school
Me: A senior colleague of mine who graduated from the school recommended it to me after which I went online to do my own research about the school. I read reviews about the school online and I spoke with some of the school's lecturers.
Vo: nods, okay. So, how many schools did you apply to?
Me: 3
Vo: which are the other two?
Me: Penn State University and university of Maryland
Vo: oh, nice. How many offered you admission?
Me: 2, Pennsylvania State University and WCU. My admission at University of Maryland is still pending
Vo: I see, so, y not Upenn (I then corrected him that it's not upenn but Penn State) ,oh okay, y not Penn State?
Me: I chose wcu over Penn State cos I am interested in an ongoing research by Prof Carson on Health disparities in underserved populations, and at present, my community is underserved health wise, I am also interested in the fact that wcu mandates mph graduate students to complete a 6 credits community service course. This allows the students to interact with their community. This exposure will help me when I return to Nigeria after my masters.
Vo: nodding, why public health?
Me: I chose public health because it is a perfect merge between my passion and my training. I will love to join hands with the federal ministry of health and other public health non governmental organisations to help reduce the disease burden in Nigeria especially those diseases that easily plaque us, such as tuberculosis, malaria, HIV... Also, on a long term, I would love to establish my own community pharmacy so that people in my community can easily access health care.
Vo: I can see that you currently work as a pharmacist
Me: yes, a superintendent pharmacist in ilorin
Vo: when did you bag your pharmacy degree?
Me: 2014
Vo: did you take gre or gmat
Me: I took gre and toefl
Vo: good, who will pay your tuition
Me: my dad and my uncle
Vo: what do they do?
Me: my dad is a permanent secretary and he's also into consultation services, my uncle is a civil engineer and he has his firm in ilorin and Abuja
Vo: smiling, I will be approving your visa,
Me: thank you with full smiles ( I almost knelt to say the thank you). I then ran out.

My advice: be positive, be confident, do not cram but practise consistently cos it is very easy for one to get hooked on a very simple question, one might just not find the right words at that time.
Most importantly, pray well. God did mine.
I wish all going for their interview the very best.