I would still try to see the doctor. When I was at 7 weeks i starting spotting and then it led to a mc. You probably won't have one but just to be safe...
If you're not cramping, you're probably fine. I know when the mucous plug starts to form (which happens in the seventh week), it can cause some streaks of blood to pass. If you start cramping, go to your local ER. Otherwise, breathe and relax, you're doing great!