Does Dark Mole On Arm Indicate Melanoma?

Hello, i recently showed a doctor a dark mole i had on my arm, about 4-5mm almost black. to me it looked round and all one colour, however it was darker than the rest of my moles. im not sure how long its been there, but at least 6months. he has since removed it and im waiting results. im so scared its melanoma and im going to die.