I honestly don't remember much pain. But I do want to tell you that one of the side effects is poor night vision. Lights are more blurred, etc. I always wear anti glare glasses when I drive...and it make me less likely to drive at night. That was definitely a downside.
That has changed for most patients with modern scanning-spot lasers. They are now able to treat a larger area, so night vision problems are *much* less common than they were 12 years ago.
The problem is caused when your pupils expand in low light and become larger than the area treated by LASIK or PRK - you end up with light entering the eye from treated and untreated areas simultaneously. With the old broadbeam (6mm) lasers, if your pupils got larger than 6mm (mine are 8.2mm), you had serious night vision problems. But with scanning spot lasers, the treatment area is limited only by the thickness of your cornea.
I had LASIK in 2003 with a scanning spot laser, and despite very large pupils I have no real problems with night vision. The technology has come a long way.