No longer wanting the wedding and the baby

I suffered from a miscarriage at 7 weeks December 31 I went about 8 weeks with no period and actually stop trying to conceive and yesterday I took 3 test and all were obviously positive but now im kinda scared because I gave up on wanting a child. I'm trying to focus more on myself and career and I want to call my wedding off. so it's like what do i do now ? How do I tell him I don't want this relationship anymore and I'm not ready for a baby ? I think I moved too fast too soon