What should be the time difference between 2 nursing sessions,my baby is 3 weeks 4days 2day,new mom,no idea!?

If you think you have a low milk supply try pumping ... maybe that will help you to produce more milk and your baby will have less frustration when trying to feed. Also u didn't mentioned the age of your baby, but it could also be nipple confusion. If she is easily getting more formula from a bottle she will most likely want to eat that way. I guess the best advice I could give besides pumping to increase supply, other than contacting a local lactation consultant. Best of luck to you and your little one :)