When is it acceptable to make an ER trip?

Ericka

Hello! I'm almost 7 weeks Ive been feeling oretty crampy today and have had a little milky/clear discharge today. I just went to the bathroom and there was a tinge of blood on the paper. I haven't had my ultrasound yet, its not until March 13th. Im just sick to my stomach. I dont want to waste the ER's time and resources, just wondering when its acceptable to go in?