Bleeding around the placenta?

I'm 8wks and I had a tiny bit of blood in my underwear. I immediately called my ob, and he told me I could wait and watch out or go to the hospital to get checked. This being my first child I'm overly cautious so I went. When they did they ultra sound the doctor told me there was a little bit of blood around the placenta and he put me on pelvic rest. I have an appointment with my ob on Tuesday to see if it gets any better or worse. As of right now I'm really terrified that I'm going to lose my baby. The doctor said it doesn't mean that I'm going to have a miscarriage but gave me a pamphlet on possible miscarriage. It's been 2 days and so far no more blood. Has anyone else been through this? Is you're baby fine?!