I have dark pigmentation around mole removal area within a few days. Is this bad? (Photo)

I had a mole that started itching occasionally so I went to have it checked. The doctor wasn't worried but I had him remove it anyway. He did a shave excision and had it biopsied and the results were negative for any cancer. A couple days after the removal some of the area around the still open wound turned dark brown and has irregular borders. I'm a bit worried. I don't have a before picture but it was round raised mole with no pigmentation outside the round mole.