I have had a fluttering in my kidney region on the left side for the past day. It is not painful. I drink a lot of water throughout the day, work out five days a week, eat an extremely well-balanced meal, do not smoke or drink. I have noticed the urge to urinate frequently which I thought was due to the large amounts of water I drink. Please shed some light on what this fluttering can mean? The more it continues, it has made me more worried and concerned. Thanks.