A few weeks ago I noticed a mark appear on the front of my neck/ top of my chest. At first I could only see it when I turned in the light but now it is more visible. It is about 5mm across in a stretched circular shape, it has a depressed appearance and the skin seems thinner inside the mark. It kind of looks like a scar, but is the same colour as the rest of my skin. I have noticed that I am starting to get another one forming slightly higher in my neck which has led me to become concerned, however, I am not sure if I am overreacting! 
Please can someone help me identify what the mark is an whether I should make an appointment with the doctor to see about it.
Please can someone help me identify what the mark is an whether I should make an appointment with the doctor to see about it.