Nervous - TMI - no picture

Earlier this evening, when I went to the bathroom, I felt something come out of me in a clump. it was a clump of discharge with what appeared to be a spot of dark blood or possibly it was brown. When I wiped I got the same thing. Haven't had anything since but of course I called the doctors office right away. Nurse said I'm most likely fine but they want me to come in anyways in the morning to double check everything and do an ultrasound. While a big part of me feels like everything is okay I still can't help but be a little nervous. Wish it was tomorrow morning already.