Help me! My baby is up all night!

My daughter is almost 4 weeks old, she is up for 4 -5 hours every night wanting to eat , it's like she will eat 4 oz then fuss for a half hour, eat another 2 oz then repeat half hour another 2 oz. fuss for another 3 hours till finally sleeping 3 hours , Then up doing it all over again. I'm so exhausted!! This is my third daughter, but I never experienced this before! Any advice is greatly appreciated!