I had Lasik last October, and the operation itself wasn't painful. Try to get an appt in the afternoon, and get someone to drive you home and go to bed. After the operation, it felt a bit sore - I read it was like someone put chopped onions in front of your eyes, and that is what it felt like - but after an hour or so it was fine.
One of my eyes regressed though - ie went back to -1 eventually - and I had that eye redone a couple of months ago. It's called an enhancement, and was more painful, as they open the original flap, which has at least partially healed. With the first operation, they make a flap with the laser, so it's clean and not painful, but with the second they flip open the original flap, if that makes sense. Anyway, recovery was worse because of that, but I would say around 3 hours of moderate pain.
After the enhancement, I then got cells under the flap - because the flap is now more ragged, you are more likely to get these cells under the flap. In the end, this was fine, but there was a point where they thought they might have to open the flap AGAIN to clear out these cells,and I was told this could happen multiple times. I was also told that if these cells proliferated there was a chance that it could affect my vision in that eye AND that this could not be dealt with by wearing a contact lens. At this point I was really worried and TBH wondering why I hadn't stuck to contacts!
I now have perfect vision in the redone eye, and -0.25 in the other eye. I expected perfect vision like I had had with contact lenses, but that didn't happen for me (not sure if I was expecting too much). They will not redo an eye that is only -0.25 and TBH given my experience I don't want them to!
Read into it all and decide if it's for you. Check how much experience your surgeon has - mine had done 75000 of them. I am not in the UK, but if I was, I would go to Moorfields as it has a great reputation and I wouldn't feel safe otherwise (that is just the way I would feel).
My eyes are still quite dry but I just use eyedrops, and that is getting less.
Overall, I am happy with the results, and I am the only person I know of who has had issues at all!