I noticed a black dot in my belly button when i cleaned it out it came out and it was black on top and white on the bottom it was smaller than a seed ?

May be a blackhead: A person can get blackheads (open comedones) anywhere, but they are more common in locations that can have acne. First, a skin pore is partly blocked by a little clump of skin cells. The skin pore continues to stay active, producing more skin cells daily, mixed with some oils. At the surface, oxygen in the air causes the dead skin cells to darken. Under the skin, the dead cells are not darkened.