My 3.5 month old boy has been projectile vomiting about once a day for the past 6 days. He has also had diarrhea/blowouts or at least much looser stools than normal. We've spoken to the doctor a few times and they say as long s he's not dehydrated or running a fever (which he's not), that we should let it run it's course and that it may be a bug. I'm worried as he normally eats six 6oz bottles of formula a day, and lately hes been only eating around 24 oz (minus whatever he pukes). Overall, he seems happy, but I'm so nervous being a first time mom. The only change in his diet is that we switched him from Target Sensitive Formula to the Walmart brand about 3 weeks ago. he's a good sized boy and never has issues finishing a bottle where today he refused two. We did try switching him to Soy today, as both my brother and I were on soy as babies and I thought it could be an issue with formula. Could it be a milk issue, sickness, teething, other???