You know that feeling you get if you miss a step when going down the stairs? I've been feeling that for the last two days. Heart pounding, feeling shaky, etc. It was so bad I couldn't sleep last night and I'm worried that I won't sleep tonight either. All google has come up with is anxiety but I've nothing to be anxious about. Have you experienced this? If so, how long did it take to stop? It's starting to be a problem.