Nervous about ttc again.

In August last year I found out I was pregnant unfortunately I had a miscarriage and after 4 weeks of my levels dropping then going up a bit then dropping again I was diagnosed with a pregnancy of unknown location. The doc thought I might have a very small amount of retained tissue but they couldn't see it on any scans. I was given the Methotextrate injection and told to wait 6 months before trying again. I went back on the pill for those 6 months and now I am coming to the end of the supply and and about to start ttc again. Part of me is excited about the chance to get pregnant again but I  also very nervous thinking about whether I will miscarry again. I really want another baby but I'm not  sure I could go through that again. I have already decided that if I have another miscarriage then I am going to stop ttc and be grateful for the beautiful 4 year old boy I have been blessed with