Baby wakes up every hour help?

i know it takes a while to get down a sleep pattern but he is now 3 days old and his first night home he wakes up every hour. he is bottle fed and we got him to sleep no problem in the hospital. could it be a different nipple that i used at home on his bottle? that is the only thing we did different. we had to start using a pacifier too. he is asleep until it falls out then he's up again. what can we do?