Felt it in Silver Spring. At first I thought it was someone running on the floor, then it kept going and getting stronger. Funny, peoples' heads popped up out of their cubes like prairie dogs. lol Worst earthquake of my life. Actually saw the columns of the building swaying. On the third floor about 500 feet from the nearest stairwell. If the building fell, I wouldn't have made it. Hope this doesn't become a yearly thing. My nerves can't handle this.