Tremors

I was in the library when suddenly the bookshelf that I was leaning on started to vibrate. My first reaction was to look at the other end of the bookshelf to see if some kids were playing near it. Since there were none, my second reaction was to touch the steel bookshelf but it did not vibrate. Only when I lean against it again, I could feel the vibration. And then a thought struck me which nearly made me peed in my pants. If anyone of you have ever watched the local horror movie, The Maid, you would rememeber the part where the ghost sat on top of the wardrobe, legs dangling, hitting against the doors of the cupboard. So I slowly look up but of course there was nothing. Later when I got home my mum asked if I felt the tremors and I went, "YES YES YES!". She said Indonesia had an earthquake... I pray for their safety.