UserX
Did you try dissecting it?
I don't know if there is any way to say definitively what you've got there, but it's probably a good thing that it's not inside of you any more.
If the thing breaks down and falls apart easily, I'd presume it's worm nesting material.
If you dissect it, and find entrails, it's probably a big worm of some kind, maybe a tape worm.
Jesse's Mom might be able to shed some light on this. Seems like she got a couple of the heads to come out of her.