What Is The Growing Mole On The Leg With Pulsating Aches?

I have had a slowing growing mole on my lower leg for the past 3-4 years. It is pale to light brown and less than a 1/8 inch and round. It does not hurt, flake or bleed. My concern is that over the last 3 weeks or so I have experienced mild twinges to pulsing aches deep in the same leg. Off and on during the day and night. The exterior of my leg looks normal, no swelling, pain, warmth or lumps.