No worries hun.

I would assume that the placenta of Flickers twin, broke down after the sac ruptured. They were two separate sacs one on either side of the uterine septum that they had separate placenta's and that Firefly's had completely attached to the septum, rather than the side of the uterus and the septum like Flickers has, that way it was able to get enough blood flow to grow.

As some of the bleeding and clots ended up being reabsorded it is hard to be conclusive about it....

i hope all goes well today and I would be fascinated to see photos too, my own medical interest coming out!