What is his problem?? Serious Only...?

My ex (we only broke up a week and a half ago) have been dating for three months but everything moved really well and really fast. Last Thursday (he brought the subject up) we were discussing wedding stuff and getting married. Friday night he told me he thought we moved too fast and he was not ready to be in a relationship right now. It broke my heart. He asked me to give him a little time to figure out what it was he wanted...either to let go or hang on...that he didn't want to mess up and let his future wife walk out of his life. Well, 3 days after we broke up I found out I am one and a half months pregnant. I told him, and said for him to take some time to figure out what he wants because I dont want him with me out of pity for the baby. He told me last night that he can't be in a relationship with me but he wants to be there for our baby. I do not want him to because it hurts me so badly seeing him, yet not knowing what I did so wrong. He tells me he just isn't ready to deal with a relationship right now. How can I either A. get him back or B get over him. Oh..and he has issues at work that are stressing him out really bad too (he is a narcotics detective.) Advice anyone??