The discharge does die down to a yellowish colour after the bleeding stops, hon but do get it checked if you're worried. I had this a greenish/yellow discharge around 5 weeks after my section and it turned out to be an infection in my womb that i had two lots of antibiotics for. I remember feeling rubbish when i had the infection. Things such as stabbing pain in my abdomen, high temperature, nausea and dizzyness . If you're feeling fine otherwise then it's probably nothing at all to worry about. As i said before, the discharge does go from blood to yellow then clear befor it stops so it may be completely normal xx