Hay nako, momshie, please take your baby to the doctor or emergency room right away, light green vomit with 3 days of diarrhea needs to be checked immediately, especially if it's happening after every feed. This could be something that needs proper medical attention, and babies can get dehydrated quickly, so don't wait on this one, ha! A few of us moms have been through similar scares, and honestly, peace of mind from a doctor is priceless, you're doing the right thing by asking for help. Sending you strength; you've got this!