Hi there,
my DD (now 15 months) had reflux pretty badly as a baby. I just wondered what your milk supply is like? Could it be possible that her short feeds and unsettledness could be because you have Lots of milk, or a very forceful letdown? Does she really gulp when you feed her, or does milk spill everywhere because there is too much for her to handle? If thats the case she may have a tummy ache from being over full before you or she even realises it (not to mention extra wind in her tummy from gulping). I just ask because thats what happened with my DD and it makes reflux even worse. IF they are already prone to reflux and then their tummy is overfull it can be a really bad combination. I used to always keep feeding, trying to coax my DD to drink more because i kept thinking "you can't possibly be full after just 5 mins feeding" but now in retrospect I think she was probably completely full and i should have stopped as soon as she stopped.
My other theory is that 'short feeders' like my DD spend so much more of their A time actually being stimulated, rather than spending 30-40 mins just sucking and relaxing with their feed, so they end up getting overstimulated much more easily.
anyway, not sure if any of that helps,
good luck, let me know what you think.
Jessie