Scared!

So last February '15 I had a miscarriage. I have know so many girls with miscarriages and ectopic pregnancies and I'm scared about my pregnancy.. I keep getting cramps in my uterus AND my left ovary that come on and off. I have not seen any implantation bleeding so I'm worried it's in my tube. I can't stop stressing. How soon is it to find out if my embryo planted fully in my uterus?