Hello, I know this sounds really weird and it was! I was sitting at my desk and felt and looked as if we were experiencing an earthquake and I reached to grab ahold of my desk.As I did, it flipped over sideways with my computer ontop of it and I never could get a hold of it. I almost fell out of my chair.Then it just stopped.I looked down,my desk was fine,nothing was shaken up and no one in the room had even noticed what I had just experienced. My head feel tingly in the back and I know have a headache . One of my students saw it and said I said Earthquake and almost fell out of my chair as I grabbed my desk. It only lasted a few seconds.I had not taken any medication or done anything out of the norm. Thanks, Stef