C.S.
At 2 weeks 2-3 oz every 2-3 hours is normal. Supplementing is okay, just keep in mind that you can overfeed your child as well as underfeed. Unless you know there was a problem with your breastmilk that caused the weight loss in you daughter, your son will probably get enough from you. Breastmilk is also supply and demand and the more he takes from a bottle the less he gets from you. If you want to get an accuarate gauge as to what he is taking in pump and give it to him in a bottle. I would encourage you to pump after you feed him at least every morning so that you have a store of breastmilk for later. I did not know to do this with my oldest and went back to work and had to supplement with formula. ( we mixed formula in the bottle with breastmilk) With my second I was able to store enough in the 1st 6 months that he has never had formula. You can also use it when he starts eating cereal. It simple, just use a hand or electric pump after he finishes eating and start storing it. I actually did it in the morning and before bed for the 1st three months. It probably won't take you long to get a 2-3 ounces. Once you have the amount you want to try, make him a bottle with 3 even 4 ounces in it and see how he acts. He should let you know when he is finished and then you will know how much he is getting total. Also remember that babies will sometimes take more formula at a time and eat less often because it is harder for them to digest. Breastfed babies tend to eat less more often because it is so easy for them to digest. Good luck! Enjoy your new baby boy!