I need help !

My baby is a great beautiful babby but there is one bigg problems he doesn't let me do nothing . Lol. I literally take like a whole hour just to put him to sleep. He want me to carry him rock him. My arms literally hurt ass hell ! I'm the only one that can put him down hell cry with everyone else. No one knows how to rock him I alredy no how to but, what can I do ? Any advice ? I hate hearing him cryyy . He's 2months and was born 1month early . He was only 4 pounds 5onces at birth. Now he waits almost 10 pounds . 😍