Another "reply" from my UK medic friend:-
"I think the important thing for everyone to realize is that patients are all very much more individual in their response to things than most people realize.
Some will have very high pain thresholds and simply will not perceive as uncomfortable, something which for another would be unbearable. Add to that the fact that recent studies have shown that women and men tend to have rather different responses to pain and it all gets very complicated. Women tend to feel pain more as an emotion, a state of mind if you like, whereas men tend to zero in on physical sensation. For this reason there has been recent work on using different types of pain relief for men and women. Typically females respond better to pain relief that contains a sedative element.
To further complicate this there is the whole thing about there being no way to get inside someone else's head and verify that their experience is the same as yours. So what it all boils down to is that your experience will be yours and yours alone, and for that reason its fairly pointless, even if understandable, to ask about this sort of thing. The same thing broadly applies to pain in dilation, electrolysis, laser, and indeed any other treatment you may conceive of.
If I may propose the general idea, prepare for the worst, and then you will probably be pleasantly surprised when its not as bad as you anticipated. By contrast if you go in expecting to be all roses and fairy farts you will probably be horrified at how bad it actually is. This is why when injecting a new patient I won't tell them "this won't hurt," instead I will say "I won't lie, this IS going to hurt a little bit, but be brave." - then nine times out of ten it's simply not as bad as they fear and they feel ok.
I have seen people who have indeed had a very bad reaction on waking, including vomit and all sorts, in fact one girl I was with when she woke nearly died. However these are actually surprisingly rare occurrences given that this is major surgery, and I also know of people who had no vomiting, no discomfort and even refused morphine going through the whole process with nothing stronger than Acetaminophen (Tylenol to you).
Bottom line is - you want the procedure, you've been dreaming of it, so find a strategy in your mind that enables you to actually enjoy the process. Approached in the right frame of mind, even dilation should be at least marginally enjoyable. For example how long have you longed to be able to insert something there? Well now you can, indeed now you have medical dispensation to do so at least three times a day without being accused of being immorally obsessed with playing with your new bits! So how good should that feel?
Most teenage girls would love to have had six months of their life when they had license to masturbate without feeling guilty! Or you can simply think about all the wasted time and feel annoyed that you have to do this. Approach it with one attitude and the time will fly by and you will feel positive about it. Approach it with the other and all you do is reinforce the idea that as a trans-woman you are somehow hard done by - which attitude I reject.
Now you may imagine that speaking, as I do, from the perspective of the medic I am demonstrating that I know nothing about about what you are going through. Be careful with that thought. I understand more than you realize, but I am also very convinced that Positive mental attitude will get you better results than indulging in self pity."