Totally. Migration isn't always a symptom of infection or caused by trauma to the piercing. Sometimes the body just decides to push the jewellery out, and until it starts getting near enough to the surface to apply painful weight or tear, you could have what feels like a happy, healthy piercing. Your only true indication is whether it's closer to the surface than it used to be.
You know what? I'm gonna leave this bump and just lock the thread, 'cause y'all need another "fuck you, read the rules" reminder.
Also, for those of you who want to see what kind of thing counts as a "helpful contribution" that we WON'T delete, check out Speedball's post in the Subdermal thread.