I am a midwife. I also have 7 children & have had 2 miscarriages, both at 12 weeks. I, personally, would not go to a doc, esp. this early, but that's just me. It could just be implantation bleeding, but probably not, since the preg test was already pos. All a doc would do is an US, which I remain unconvinced is safe in early preg. When bleeding occurs, ad the baby is healthy, it could be low progesterone levels, so you might want the doc to check that. If you are miscarrying, the baby is usually dead, before bleeding or cramping starts, so if there is a <3 beat, this will probably pass. One of my pregnancies, I cramped the whole 1st month, I was sure I was going to mc, but never did, went on to have a healthy baby 8 months later. I did eventually go in for an US that time, 'cause I just couldn't figure out myself what was happening, but it wasn't until several months later, when US might be safer for baby.
When I had my mc's, I stayed home for both, except for the 1st one, I bled heavily afterwards, and ended up transporting for a D&C as it turned out to be a molar pregnancy, not a baby at all! The 2nd time, it was uneventful, I invited a midwife friend to help me through the ctx, & after a few hours passed a clot containing the embryo. It had grown only to a 5 wk size, even though I was 12 wks, so we figured it had already been dead for 7 wks, before I had any sx. The girls decorated a shoe box while the boys dug a hole, while I got cleaned up & dressed. Then we had a funeral procession into the back yard, said some prayers, sang a hymn and buried the baby along side where it's brothers & sisters placentas had been/would be buried.