Hi Vix,
I don't know the science of it, but I found the Gax X to be a big help. I did have shoulder pain for about a week. It was worst the first day or two. Walking really helps with the gas pain, imho.
I have some gas tonight, feel like I need to burp, but I drank my liquids too fast at dinner. I knew I was doing it, but for some reason, didn't stop. Tomorrow I start solids and I know going slow is going to be a challenge for me!