It is normal that your are a bit nervous about doing a flush. I literally don't know anybody how did not feel the same.
I did 17 LF's so far and can really recommend this type of body cleansing. According to my experience it is important to talk so somebody who did LF's before or to read some testominials here in the forum.
The Liver Flush itself is not painful at all. However, it might be possible, that you will feel very tired and drowsy the next morning. That are all the toxins released by the liver. So,it might be a good idea to get some experience with enemas before doing the actual flush. An enema first thing in the morning after having the oil juice mix the night before is so important, because you get rid of a lot of toxins immediately. five ore even more enemas in the course of the day are ideal if you really want to take the full adantage of a liver flush.
Be also prepared that the first flush results have a horrible smell. I might be a good idea to choose a weekend on your own for this procedure.
A veggie broth for "recucitation" around noon I found very helpful for replenishing all the minerals lost during the flush. Try to prepare something around half a gallon of it. You will be very thirsty and you definitely should make sure that your water/veggie broth intake is quite sufficient.
A warm bath of one hour filled with half a kilo of baking soda between ES serving 1 and 2 worked wonders on me. It helps relaxing and the more relaxed you are the more stones you will pass. Believe me.