I was just waxing right now actually XD Lol
I'll tell you this, brows are the part that hurts to least. Feel your forehead and you'll realize that it's not an overly sensitive area and it's pretty strong, so the top part wont hurt. However the lower part, like the arch area, will hurt depending on how thick your brows are and how close to the lid area. It'll sting just for a second - honestly, no longer and your eyes may tear up, but it's just from the sensation. I'm Greek, Armenian and from Turkey XD so I've grown up with waxing
As for trimming...oh man I accidentally took a chunk out of my brows the other day but anyway, it actually helps to THIN the brows out...it's hard to explain but you're not gonna be plucking just layer it. Ask the lady, she'll get it. Ask her to thin out the hair NOT the shape of the brows. Like cutting over on top of the brows to thin it out.
As for making your brows pink, there are some temporary color gels you can put on your hair, use one of those. Gloop (lol) it on there really well, and it'll work. OR just dye them...honestly, it grows back within a week, our brows and lashes fall out constantly. Bleach your eyebrows and go over it with hot pink. Or you can buy one of those hot pink dye packs from Hot Topic, they have bleach in them.
I had my hair bleached last month (I'm a chocolate brunette) and my roots grew back so fast...and as for the brows, even faster...naturally, I'm back to being chocolate, it was such a bother to bleach every week. After the con, you can just dye your brows black again, no problem.
Sooooooooooooooooooo yeah, hope that helped.