Did you have surgery or did you miscarry on your own? Either way, I'd give yourself until Monday to return to school. It's easy to overdo it and not realize it until the next day when bleeding picks up. I've had 2 D & Cs and the first one I had surgery on Tues and was back to work on Thurs. The 2nd one, I had surgery on Weds and waited till Monday to go back to work.
I've never miscarried on my own, so I can't speak from that experience. But I'd say just for the mental health of it, give yourself the time until Monday. I'm so sorry for your loss...
at 9:16 PM on Feb. 16, 2011