I had bleeding when I was about that far along. I was in a panic, tears... I left work and called my OB wanting to come in right away.
He explained to me that at this stage there is NOTHING that they can do to save your baby should there be a problem. There are no drugs or procedures they can give you to avoid a miscarriage at 8 week - if it has already started.
The bleeding could be completely innocent (it was in my case) or it could mean a miscarriage under way. He advised me to take it easy and make an appointment for an Ultrasound and if the bleeding got heavy (soak a pad in an hour or less) to go to the ER.
As I said, in my case everything turned out fine. There was a hematoma (basically a bruise) under my placenta and I kept spotting for a few weeks until it was resolved. Baby girl had a strong heartbeat and was born perfectly healthy.
I would advise that you call your OB and see what they say, at 8 weeks they should be able to find a heartbeat by Ultrasound, that could really put your mind at ease.