Supplementing and pumping?

My Lo is 4 days old now, she was jaundice and not gaining enough weight so the dr told us to start supplementing. Ive been trying 15 mins on each breast then giving a bottle and she seems satisfied. I will occasionally just give her a bottle when im too tired, too sore, or daddy is watching her while i rest (if she takes just a bottle she eats about an oz, if both she eats about half an oz or a little more). Since yesterday her jaundice has gone down and she gained a whole 3 oz! They want me to continue supplementing since my milk still hasnt come in. I am getting a hand pump tomorrow to try and help my milk along but should i give her the milk i pump? Or store it? I feel like if i have her nursing, and try to give her my pumped milk and supplement her with formula it will be too much? Any advice ladies? I almost just want to give up and formula feed since thats the only time shes full and happy but i feel like a failure 😭