I remember feeling exactly like you did but my midwife told me not to use a dummy (don't go there) and it turns out I had an undersupply of milk. Are you breastfeeding? Perhaps if you are, give her formula for one feed and express the time it would take you to feed to see how much it is, and whether it appears to be enough. Maybe ring the ABA and ask. Sorry, I'm not trying to get you to FF or exclusively BF, just an idea.