I am a 29 year old female. Over this past week and currently I have been experiencing this weird vibrating/fluttering sensation in my left side up behind my left ribs area. There is no pain and I am not pregnant. The sensations last about 5 seconds and stop for about 10 seconds and do 10-20 reps at a time all day long. I am under no additional stress than normal. I am not really worried but just curious. Thanks for the help.