With the dermals just make sure you go to a skilled piercer who can show you pictures of HEALED microdermals that he/she has done. And when considering placement make sure it's not an area that you normally wear your pants. My hip dermals healed pretty well and I think they're one of the sexiest piercings out there.
Was your navel done with clamps? I always find piercings done with clamps to be more painful.
Congrats!