CIO Method

Has anyone tried the Cry it Out Method, if so how exactly did you go about it and did it work? I tried it for the first time tonight and baby would cry (not scream) for about 15 min and then fall asleep on his own. However he would wake up like 30 min later, cry for 15 min and go back to sleep...and so on. After him being down for 7 hours I finally got up during one of his cries and changed his diaper/fed him. He's 15 weeks and I'm a FTM and have no idea what im doing, just wingin it over here 🙃