How To Treat Light Vaginal Bleeding,back Pain And Cramps During Pregnancy?

Hi I am 28 years old and just found out that I was 4 weeks pregnant last week. My doctor did an ultrasound and seen a sac, my hcg levels have doubled, but I am having some light red and dark brown vaginal bleeding. I am also having alot of back pain and pretty bad cramps. The past few days I have also felt alot of pressure at the bottom of my stomach. My doctor said this could be an early miscarriage or a high risk pregnancy. I'm thinking to see if I can get my pregnancy medically terminated. Do you think that's a good idea?