Sound like implantation bleeding. I had bleeding seceral times with my first bub and she is almost 1 now.
sorry for tmi but sometimes sexual intercourse can cause bleeding too!
Look up implantion bleeding BTW. It might easy your mind.
Implantion bleeding probably. But you are very early in so your still in the danger zone. Definitely try not to stress to much that can make things worse. All you can do is wait and go to the doctors. Good luck.
I've never heard of or experienced it but that doesn't mean it's not normal is call your dr just incase he may want to check your fluids and everything