Ok I'm having a really weird feeling and I don't know what it is. Baby is moving around I think but…

Ok I'm having a really weird feeling and I don't know what it is. Baby is moving around I think but sometimes it feels like she's literally shaking for about 10 seconds straight. It's too fast for hiccups. It's happened about 3 times in the last 30 minutes. Does anyone else ever feel this? Please help!