at the begining, my baby also 食完一小時又口"猛猛", so i fed him formula afterwards, but eventually we succeeded in complete brestfeeding. :lol:
i seldom stored milk since i always want him suck my nipples directly which can stimulate milk production & i enjoy this close mum & son relation very much. but once i did need to pump milk for his night feeding in the hospital. for better hygiene, i wash and steam the pump every time after use & then keep in the refrigerator. i stored milk in either breastmilk bags or nursers without nipples.
once i also went through the difficulties you're facing now and i did feel frustrated very much and even thought of giving up.
but after more practices between us, we achieve it, so DON'T GIVE UP, KEEP TRYING, KEEP TELLING YOURSELF THAT BRESTMILK IS ALWAYS THE BEST.
i completely understand that as a mum, we always worry our babies not taking enough milk, but gradually you will get it by observing their diapers. :)