Dear brother, I can't help much but I am in a similar situation like you. I have cleared a test too and my interview date has arrived but I don't have any idea as to what awaits me in the interview room.

I am not medical student or anything either so can't help much.

I think they will ask you questions as per your latest degree (As told to me by Mr. Ali Mallah) and related to your subject and then the general knowledge.

Last but least, It is Allah's decision if you get it or not. Something bigger is always next.