Is this normal for a 1 month old?

My bby is 1 month old and 5 days, he's a breastfeed baby but I've just started him on formula yesterday so he does both. Anyway at night he wakes up to eat so I breast feed him, burp, and change diaper. Then after words he's wide awake but when I try to put him to sleep he crys like he's hungry again so I feed him again burp and change. He's up for about 2-3 hr is this normal?? And its been like this for the last 4 nights so its not cuz he's on formula now. wut can I do to get him to go back to sleep after he eats at night? Also he hasn't always been like this just in the lst 4 days