Do not be afraid of how much painful it will be or not.
Every woman is different and every delivery is different in the same woman.
How long labor will take nobody knows. It depends on how easily you dilate but that will only be discovered in labor day.
first deliveries are usually longer.
dont stress too much about the subject, it is natural that you are afraid but try to relax. It will help you at delivery time.
Try to forget about the circumstances and try to have a pleasant delivery and not a traumatic one. This will help you if you decide to have a second child some other time in your life.
Labor may be tedious but dont be scared. You will be sorounded by professionals who will take the best care of you and your baby.
about what it feels, it is the most incredible experience you will ever have. I was paniked about delivery with my first one and after having her I felt relieved. Dont believe that crap in movies where women scream for hours and hours like if they were dying. It is painful yes, but nothing you cant handle. Labor will take some hours but the painful parts are only when you are reaching the delivery time. that is when the baby has started to go down and shortly after that it is out.
In my both kids it was for about 2 hours before delivery. the rest of the time it was strong crampings like when you have your period, but nothing you cant handle.
Once the baby's head starts coming out, delivery itself takes only a few seconds. They slip like gelatin in two or three seconds with the last push.and you feel almost no pain there and when the doctor puts him/her on your chest still with the umbilical cord uncut and you kiss him/her for the first time, believe me your whole world will change forever.
Best of luck
PD: dont panic about the baby's size and how it will come out through that small hole. When the delivery date is near, the body has its own ways to prepare for the expulsion of the baby. It starts producing some hormone( i dont remember thename now) which will make your vagina muscle dilate to the max to allow the baby's head come out. It also lets you open your legs wider than normal. Dont ask me how it works but it does.
Dont have nightmares over this. It is a natural thing and it is the only way nature works for giving birth. Nature is wise.
The day will come yes or yes and the baby will eventually come out. It is natural to have fears but try to relax.