Is she drinking well?

My baby is 1m & 20 days old. She's 4kg. I breastfeed exclusively, no pump. We give her a bath at around 8:30 am everyday after which she sleeps for long stretches. I try to wake her up 11 but she is sleeping so deeply, it often takes me 45 mins to wake her. It is exhausting. After which she drinks for about 10 mins before falling asleep. I wake her up again at around 2 in the afternoon and she again drinks for abt the same time. Today I woke her up at 4:15 and she drank for like,3 mins before going back to sleep. Im worried it maybe too less but I don't know what to do. Trying to wake her to feed isn't working. If she does wake up, she's fussy and cried. From 6 in the evening I feed her almost every hour till she falls asleep at 12 Am. Then she wakes up at 3 where I again feed her almost every 1-1.5 hours. Am I doing something wrong? Is she getting enough? Im honestly worried abt this. I feel like she's drinking way less than other babies. But I have no one to ask. Please help.