This does indeed sound like a small mole. As you know, moles are formed from the collection of small pigmented cells, called melanocytes, under the skin. Moles are normal, and everyone has them! However, each mole does have the rare chance of evolving into a serious type of skin cancer, called a melanoma. It is therefore important to keep an eye on your moles and let your doctor
know right away if you notice anything suspicious about your moles.
In particular, things to look out for would include: asymmetric moles (the two halves look different from each other); jagged or irregular borders; changes in the color of the mole; size greater than about a pencil eraser; any bumpiness, elevation or change in texture of the mole. If you notice these things (for example, if the spot on your neck was previously dark and now is blue) then that would be a sign to go see your doctor.
Your doctor can take a good look at the spot and decide whether they agree that it is suspicious for melanoma. If so, then the mole will need to be removed by a simple office procedure. A dermatologist
can do this for you, and some primary care doctors
also perform their own mole removal procedures.