Lump on ear cause by nail dirt?

Patient: I am a tweenage girl that has a small, flat lump on her ear. Ever since I was little, I have been scratching my ear the same place where the lump us. I didn’t realize it, but slowly, a lump began to form. I’ve been scratching it until I had a small cut ere and now it is a scab. What should I do, go to the doctor or leave it in?