What's people's advice on mixing boob and bottle at three weeks? My daughter was feeding practical every 45 minutes yesterday and seems to want the same today - as well as being tired I am extremely sore! (Selfish I know!). We tried cup feeding her some expressed milk yesterday but she wouldn't take it. I was considering syringe feeing her a bit of top up formula milk or maybe a bottle but I don't want to confuse her and have her refuse the boob - I'm guessing it's a growth spurt and there are no issues with her putting on weight! ??