No clue, perhaps an infection? Maybe you should contact your Doctor about this.
Maybe it's your body adjusting back to normal... sorry I really don't have any other ideas! :) Hopefully it will clear itself up and if you're concerned then I agree with the previous poster... call your dr.
I don't know that there's a difference postpartum. I normally have ewcm for 4-6 days b4 o. Estrogen is responsible for the cm, maybe your estrogen has increased?
Another thought. I have always heard the most likely time to get pg is after mc or birth. Perhaps your body is saying it's really wanting to conceive again :)