My son is 4 months old now. When he was about 3 weeks old he became quite colicky specially at night…

My son is 4 months old now. When he was about 3 weeks old he became quite colicky specially at night time. So the only way to calm him down was to rock him and now he still needs to be rocked to sleep to be calmed down. This is my first baby so I'm not quite sure what to do. His doctor says to slowly wean him off of being rocked. But I'm not sure of any other ideas on how to get him to calm down and go to sleep on his own. Self soothe does not work because he will legit cry forever. He's spoiled. So me and my boyfriend kind of did that to ourselves. It's just getting hard to rock him all through the night because we don't get sleep plus we work and plus I'm also in school. So if anybody has anything to help me out that'd be so great!