Some babies do experience this just it isn't very common. This happens also when they cry as crying is tiring for a baby and they immediately konk out for the count. My baby did this when she was younger after a vaccination. You can dream feed her but in my case I just let her sleep and let her wake up when she did realize she was hungry.Read more
try dream feeding (doesn't necessarily need to wake baby up). sorry no idea if babies normally sleep more after vaccination. but mine didn't experienced that.
I feed only after baby wake up