Baby is 12 days old. she is sleeping just after 5 mins of feeding and will wake up after 20min. is it normal?

A. make sure that you try to to feed for longer time duration. Like 15-20 mins each breast. So what happens is This way baby will get balanced foremilk and hind milk. Foremilk comes in the beginning for 5-10 mins then comes the hind milk which is rich in fats and can help baby gain weight. So always empty a breast each time duirng feeding. Always try to feed for longer hours that is very beneficial to the baby.