What Causes Numbness In Buttocks?

Hi there, I am a 35 year old woman. My current weight is 151 pounds. I am about 5 foot 4 inches tall. I have lost about 100 pounds and have recently joined a gym to keep up my progress. However, a couple of weeks ago, while shaving my legs, I noticed that my right inner shin is numb. Almost like it has been numbed with novacaine. I can tell there is pressure put on it when I shave but it is numb to touch. Any suggestions on what or whom I should see pertaining this problem?