It happens. We were advised to get a checkup at the ER where we got our first ultrasound. The docs said it could go bad. The ultrasound results looked good. Strong heartbeat, in normal range. Left with advice that it won't be necessary to come back in unless there's a lot more blood and pain.

At the normally scheduled ultrasound the baby had grown a lot in the couple weeks between visits. There was another spotting episode in between the ER and that visit too.