Can someone help me ease my mind?

This morning I woke up and wiped and there was the faintest pink. So faint it was hardly noticeable. It only happened once, but it was enough to worry me. I called my OB and they are seeing me tomorrow. I’m only 6 weeks so I’m afraid they can’t do an ultrasound, so I will have to wait 24-48 hours for blood results. Even though it only happened once, I am still so worried. I haven’t had any cramping or anything and I haven’t had anymore pink when I wipe. Has anyone else had this happen to them? Someone please help and share their experiences.