In many cases a change is usually harmless and can be ignored. But, if there is redness on your skin then you should be concerned. You should keep an eye on this change and check it daily. A handy way to monitor changes is to mark the edges so you can tell if it’s growing or shrinking. Redness might require you to pay a visit to your doctor, so at the very least you should call and consult them on any skin color changes.