Should I be contacting my OBGYN now or is this something I can discuss at my 6 week appointment?

I had an emergency c-section 12 days ago, and in the last 5 days or so I have noticed the Lochia bleeding turning a dark red/brown color, becoming slimey, and it now had developed a foul smell. Also it hurts to urinate. It burns slightly (but not like an UTI) as well as a pain in my uterus almost like a mini contraction.