Spotting- help

Erica
Is it possible to have brown spotting 3 days after a TV ultrasound at 9 weeks? I also had sex with my husband 6 days ago.
As I was doing the ultrasound, the tech asked if I was spotting and I told her I had just started that morning. Which was really weird. It was really light brown the first day. Now it's dark brown. 
I've been to the ER for spotting twice at 5 weeks and 7 weeks and every time, they tell me I'm fine. 
Has anyone else experienced this? I don't want another ultrasound at the ER, because if I'm fine, l'll just spot again.😔