Spotting at 6 weeks but no cramping

I've been spotting very lightly the past two days only when I wipe after going to the bathroom. I didn't worry too much because the doctor said it was likely from a bladder infection. This evening though I wiped and it filled the toilet paper with brownish red spotting. I have no cramping at all. I spoke to the doctor and am going in tomorrow for blood tests. Just had a miscarriage 3 months ago. Can't bear doing it again. Anyone have a similar experience with a positive outcome??