Don't know whether you followed my saga last weekend, but I had heavy dark brown spotting, with some light pink mixed in there. I'm glad you got in touch with your RE and didn't have to go the ER route (which threw me into a complete tailspin).
Is your RE open over the weekend, in case you want to go in?
I was advised to sit around as well - and drink lots of water.
Hang in there, hun.