getting pregnant sooner than 2 weeks after a miscarriage?

La

I got pregnant the week I had a miscarriage.... I didn’t think you could until 2 weeks after. The doctors are as shocked as I am. Is this possible? Have this happened to anyone else? My miscarriage started July 13th and they are saying I conceived July 18th. I didn’t have sex during my miscarriage so I’m really confused. Some one help me with guidance!