Pregnancy levels

I'm pretty confused with how pregnancy levels work and what's normal and what's not. I had a miscarriage last month and found out on Monday that I am pregnant again with a new pregnancy. I went in for blood work and it came back that my levels were 52. Not sure if that's good or not. All the nurse said was that im very early which is want we expected. We were thinking that I am around 4 weeks. Anyone have any idea id my levels are normal? Should I be concerned? Going back for more blood work in about a week.