Congratulations on your new Little one... I have a 10 week old. A lot of people have told me that they get the upset stomach because they are so new to food and their body is getting used to it. I am breastfeeding so I have to be really careful with what I eat. My daughter wasn't pooping either, when I called the Doctor they told me it was normal especially for breastfed babies because their body was absorbing everything it was taking in. I had a hard time beliving this. I went to the chiropractor, and he told me it wasn't normal and recommened a couple of things. First he told me to uit eating cheese and all dairy products. Within a day or two of not eating dairy, she was pooping a few times a day. The second her recommened was taking probiotics, which can even be given to the infant in small doses. I Prefer to take it and let her reap the benifits through my milk. Probiotics introduce healthy bacteria into the stomach and colon. I think the brand he recommended was Medigenics which you can get at whole food stores or Pharmica had it as well. I also use milicon which works well, she loves the taste and I haven't been able to find any negative feedback on it. Then there is what my grandma recommends... Old wives tales LOL, but she say to put a little spit in their belly button, I have tried it, and she really did start to pass gas and feel better. Hope this all helps... I am a first time mom as well, so this is all very new to me as well. One thing I would recommend also is taking your baby to a chiropractor, One that specializes can do wonders. My baby wouldn't turn her head to the left very much, I really hadn't noticed till he pointed it out, now she has full range of motion, sleeps better and just seems happier overall. They also have a machine that can look at her nerve stuff and if there is any blockage, then they can fix that, I have heard that this will help to ensure your baby doesn't end up with ADHD... (which I think is over diagnosed) but the craniel sacrial massages really are amazing!!!