Exes and fuck ups

My boyfriend (at the time)and I broke up cuz my grades sucked ...We still talk as friends ..I saw him at the park while I was babysitting and we kissed ...April fool's came around and I pregnancy pranked him !! He knew it was a joke the whole time ...I told him that the guy who even could have been the father( who is more of a friends with benefits) didn't find it funny ....And apparently it broke said ex boyfriends heart .... ...He said that he wanted it and that he wanted a full life with me ...I feel like shit and don't know what to do ...HELP !!!!