Question: breastfeeding, baby always wants to eat but not to sleep

I am a new mom. My baby is 4 weeks old now. She is easily falling asleep during the nursing. But once I put her in the crib, she wakes up for feeding. She does this back and forth for a couple of hours. Sometimes, it’s during the day and sometimes at night. I am exhausted to feed her all day and night. Anyone knows what to do? Or who should I ask? I haven’t gotten enough sleep for a long while. I am super exhausted and even a little depressed now. Thank you.