What to do if i have a changing mole, but is it cancer or just a scratch?

When in doubt - eval: American academy of dermatology: asymmetry: 1 half is unlike the other. Border: irregular, scalloped or poorly defined. Color: varied with shades of tan, brown or black; or white, red or blue. Diameter: > 6 mm. Evolving: mole /skin lesion looks different from the rest or is changing in size, shape or color. An irregular mole that itches, bleeds or is painful is worrisome for possible cancer.