The first time I saw a girl "in real life" with nipple piercings was at the Zephyrfest (like Lollapalooza but better in my opinion) in 1994. I loved it, thought they were very very sexy, and wanted to get pierced so bad. At age 24, I finally had both done (12 years ago). It kinda hurt, but not nearly as bad as I was expecting, to get them pierced. I went to a shop that had the best reputation in town, and it was fast, simple, remarkably comfortable (I wasn't embarassed or freaking out). However, although I was extremely pleased with my left nipple, my right nipple hurt a lot (A LOT) during the healing process. My left nipple---it heightened the sensation, to this day, I'm very sensitive there and love it. My right nipple---it took some time to get anything but pain back. After 2-3 months, I could enjoy my right nipple. Big, big warning which should be common sense, but my mistake: before it heals, DO LAUNDRY and DO NOT run out of "regular" bras so that you're forced to wear a "date bra". The ball on my ring got stuck in the lace of a "date bra" before it was all the way healed, and I swear I was singing opera like a cartoon character. Not happy.
All in all, I was happy with my piercings, but 6 years later (in 2006) I had to take them out, once I was about 5 or 6 months pregnant. Interesting that the breast milk came out like a sprinkler system out of all 6 areas instead of just normal....I hadn't really thought about milk coming out my piercing holes. After breastfeeding, you have little hands grabbing, so it's taken a few years (2 children) to be able to think about that again. But I'm over it by now. Been there, done that. I asked Jeremy if he cared, and he didn't. He liked them (novelty) when they were in, but he likes me fine without them, and said he wouldn't recommend it again since it wouldn't be so novel again. (And there's a waiting period of over a month for me to heal that I don't think either of us are interested in).
One thing though: a girl I worked with back in the day had what they call a "blow out"? Messed up her nipple pretty bad. Yipes! I don't know all the details to that, but it doesn't "work" now.