Slightly bleeding/spotting at 15wks 5days

So this morning I woke up and used the bathroom and noticed there was some slight blood when I wiped, I then sat there and tried to pee again and notice almost like a period flow go into the toilet.I put a pad on did not soiled through and then it taper off to more of a brownish color (spotting).I called the dr on call and she said everything seemed ok from my symptoms of no pain or cramping.She stated something about the placenta touching the uterus and this could cause bleeding I forgot to mention I had intercourse last night.As we all want the reassurance by u/s and hb she said to call my doc office Monday am....but if things changed" like got worse" cramping or still bleeding to come in to ffx hospital.