Child support? Should I

My sons father cheated on me and so we broke up a week before I gave birth. In the beginning he would come see him everyday even took off leave from work to help me out...but then he started working lots of overtime so that he can save for a house and build his life . He makes more than double my salary and I provide pretty much everything for our son. The only thing I can say he will consistently purchase is diapers but... you all know it takes more than diapers to raise a baby. He was strictly breastfed up until about 3 months ago and now I'm incorporating whole meals into his diet as he approaches 1 year. I have purchased everything (outside of diapers) for him. I'm the one taking off from work every doctors appointment and I schedule them on his off days and he still doesnt come or will make up some excuse. He does come to my house to see him but not consistently as he likes to put in for overtime whenever they allow it.he goes days at a time without seeing him and then stops by for a couple hours and leaves. He thinks because he does see our son... at all and buys diapers that he shouldn't have to pay child support. He thinks I'm being a bitter baby mom and has even had his mom disrespect me about saying I'm putting him on child support.He tells his family a different story then what he lives.