for the clot i have no idea, but for the engourgment, i would pump to just realive the pressure and to feel more comfortable
bumping incase someone else may have better advice.
Try to take a nice warm sitz bath, where the water isn't so high and you can use epsom salt with it. Then go back and forth to see if the water can remove the clot for you, if not then I would suggest seeing your doc.
The breasts will continue to be rock solid for a few more days. It is called engorgement, and it can be pretty painful. Nice warm water from a shower can help relieve the pressure and pain from that as well.