Our little guy turns 4 months this week and has gone from sleeping through the night to waking hourly if not more when we are getting him down. Once he wakes up he cries until we rock or feed him back down. I am exhausted and will take any advice that doesn't mean letting him cry.
Have you heard of the 4 month sleep regression? This sounds like it! My guy was the same way for a few weeks... I've heard they can last anywhere from 1-4 weeks. Not much I could really do but whatever you do, don't change things up to much. Stay consistent, it'll pass!!
Re: Baby wakes up hourly - HELP!
ETA: look up bed-sharing safety if you go this route