I got my belly button pierced three weeks ago and my ball wasn't tightly on. After I loosened it, I dropped the ball and lost it. Now I can't get another ball on it for another hour or so. Will my hole close or should it be fine?

Hold up, so only the ball is missing but the bar is still in?

As long as the piercing is still in, then I can't see how you'd have a problem with the piercing closing.

The only issue is the bar falling out (which will likely happen if you're walking around without the ball securing it.

Maybe put a plaster or some tape over it to hold it in place until you can get hold of another ball?