Feeding one month old


My son is 5 weeks old, how Often should he be eating?

He eats 4 oz every time he eats. Is every two hours too soon? Usually it’s every 3 hours or 3 & hAlf but lately.. especially during the night, he wakes up every 2 hours and cries I mean he seems hungry he follows my finger when I put it up to his cheek .. but he is spitting up a lot.. but he is also drinking is VERY FAST. What should I do?