It was two earthquakes -- one "small" one and another "big" one that followed about a minute later.

On TV, they were announcing the quake intensity of the first one and and there was a video feed of the Fukushima nuclear plant, as they usually do when there's a strong quake in that area. A moment later, the feed was shaking violently -- I thought it was a replay of what was taken earlier, but it must have been the "big" one.

In Tokyo, we felt the secondary wave of the first overlapping with the primary of the second, so it was disorienting and scary. Although the quake intensity itself wasn't serious in Tokyo.