14 wks 6 days and dc

So i had a scheduled appt this morning. When i had to leave a urine sample and used one of those wipes to clean myself with i had a reddish brown string of dc come out. It wasnt much but the color worried me. I got back to exam room and told nurse and dr. Found baby hb with doppler but he had me get a ultrasound to make sure no bleeding which there wasnt. I told him my urine always reaks but no burning or itching so he is sending urine off for culture. He didnt seem to care about the dc but with me having 4 previous mcs it concerns me. While i was getting US the tech told me the cramping and stretching could cause spotting. Idk. Just so concerned since i had a second trimester mc last yr. anyone have this or advice?