Hi, I have had a "flat" mole on my left leg since I have been a little kid. Just recently it's gotten darker, but not black. A couple of days ago I noticed some dryness around it, and I scratched it. I now have a scab on the mole and it appears to be lighter. Also, I have been having muscle pains around it, but I'm not sure if that's just a coincidence. Should I worry?