Not a bad start. It's always good to see gaping/big insertion/prolapse stories, so I'd definitely like to see what direction you plan on taking this story in. I didn't notice any spelling or grammatical errors, but I do have a small technical point: if what I'm reading is right and her cervix is the end of her prolapse, then the visible part should be referred to as the vagina, and not the womb, since that's still on the inside. Having a prolapsed womb would require pulling it out through her cervix (which shouldn't be hard in its current state; maybe something for a future chapter?).

Anyway, looking forward to the next chapter.