Just read your message, personally I think it sounds like reflux. My DD done the same as your wee one! I switched to formula and it settled the symptoms for a time and then it flared up again! After a week of her not feeding I took her to the Dr and she prescribed ranitidine, which worked for a time, she is now on Losec and she is much more happy!

I would suggest that you note down when the symptoms appear and see if there is a pattern to them, like the others said, when does it happen? when BF what have you eaten?

It doesn't say where you live, I would take a look at Welcome to Crying Over Spilt Milk Gastric Reflux Support Network NZ for Parents of Infants & Children Charitable Trust it will give you some hints and tips as well as what to look for. Another thing you could try is Infant Gaviscon.

Best of luck!!!