Bloody discharge

I'm 14 weeks, and just had some bloody mucous like discharge when I went to pee, it wasn't alot but some of it was brownish and some of it was red. I called my doctor and he said he didn't feel like I needed to go to the er at this point unless it got worse or I started cramping. I did have some bleeding around around week 8, which was more like a period bleeding but an ultrasound and pelvic showed everything was clean. My question is whether anyone else has experienced this and has any insight into what it could be? The on call is from a different office than the one I go to, they rotate, but he wasn't very informative and I'm slightly nervous about taking advice from a doctor over the phone that I know little about and knows nothing about me as a patient. Any advice or insight is welcome.