pigmentation

Can pigmentation appear as dots?

It was a light brown, small, circular dot, but it grew darker, so I thought it was just a dot and tried to remove it, but it faded again in a few days.

I went to the dermatologist then and they said it was pigmentation, but I've never had acne or scars on my face, so I don't know why I got pigmentation and why it gets darker and then lighter. Is there a way to get rid of this?