My little one started doing the same thing right around the same age! And it was driving me crazy. Poor thing wanted to eat but would scream and push away, or gurgle and choke while trying to swallow. Almost was like her breathing was 'off' - she couldn't coordinate breathing with sucking/swallowing. Didn't know about the BW forums then...and wish I had!
Two thoughts:
1) I've now realized that when my LO does this it's because she's overtired. Usually because schedule has been thrown off (by a too-short nap or otherwise), so there was A before the E. In my case, I think this may be exacerbated by her dealing with a fast let-down and flow. Now, whenever this happens - which thankfully is not very often anymore, since I've gotten better at reading her signs - I just put her straight to bed for either a nap or the night depending on the time.
2) My daughter was also diagnosed around the same time with reflux - she was a somewhat silent refluxer so was in pain even though she wouldn't always spit up. (This was evidenced by the pediatrician's examination of her throat which was red at the back.) Ped thus prescribed a medication for motility as well as an acid blocker, and both seemed to help quite a bit. In fact, now at 3.5 months, she's only on the acid blocker and seems pretty happy.
Hope this helps!
Best wishes,
Katherine
although i can only speak from my own experience (and