What can i do to get my 4 1/2 month old baby to sleep through the night?

My little guy wakes up so much i'm losing my mind. He goes to bed early and the first few times he sleeps for 3 hours at a time, then by between 1 and 3 am he has been waking up every 1/2 hour to 1 hour. It seems like there is something like discomfort that is making him wake up(?) I am feeding and co-sleeping. I try giving him the pacifier some times now when he wakes up. Some people are telling me to stop co-sleeping because he is smelling me but i am wondering if it's possible to do without stopping co-sleeping.