Funny, I haven't peeked in here for a while and end up seeing two nipple piercing topics at the same time. Small world or something.
My Master had my nips pierced 2-1/2 years ago. We knew they'd be used hard, so he had the piercer set them deep, right at the line where they grow "upright" from the areola. The piercer used a curved needle to set them even deeper. They healed well and easily, and I could tolerate minor tugging on them within about 6 weeks. I can hold 2 ounce weights on them now. Frequent "use" seems to promote better/stronger healing. Once in a while they get irritated. When that happens I go back to my initial surgical steel jewelry, do daily sea salt soaks, and apply a drop or two of lavender oil in vitamin E to the jewelry and work it through the piercing. That soothes and helps them to heal again.
I love these piercings! I have labia and hood piercings too, but I think these are my favorites (maybe cuz I can see them without contortions). Master enjoys them very much, too. They're not the easiest in terms of healing (my hood was fine in less than a month), but I think they're pretty and fun to play with. If anything, my nips got MORE sensitive (mixed blessing there). Be sure to research your piercer thoroughly. Find someone with experience and (even better) positive recommendations.
I wanted to add, I was a total ninny about the intiial piercing. Master allowed me to safeword out of it twice before he kind of tricked me into it. We went to the piercer to have my hood jewelry changed and he gave me that "look." He said I could just have one pierced, and remove it in a month if I really was unhappy. I had the second one done two weeks later, AND the piercer allowed Master to do the actual piercing. What a rush!