Hi!
If you were my patient, I would want you to call me and I would want to bring you in for an ultrasound. (I bet if you call your doctor and tell him/her that you are bleeding they will get you in sooner). Although spotting in early pregnancy isn't "normal" it is common, and not necessarily a sign that you are going to miscarry again. I would want to know about the bleeding if I were your OB doctor though.
Good luck!
Dr B
It could be implantation bleeding, but as it has gone on for two weeks I would get checked out asap. If the tests are still coming back positive and you've not had any clots then that's a really good sign. As you are worrying about it I would get checked over for peace of mind.