I was going to mention possibly seeing a Chiropractor like buliej mentioned. Apparently it's very common for babies to require minor adjustments and it can help them feed enormously. I had my DS adjusted when he was quite young by a friend of mine who is a children's chiro. She could tell I was nervous about the adjustment so she showed me how hard she pushes and also used the activator on my arm first to show how soft it was. I was amazed that it would even do anything with such a soft touch, but DS seemed to get less wind after he had his adjustments.

Now that I think about it I want to ring her and see if she'll come and check DD as well