Mystery snail gender swap?

[MysteryShrimp]

So originally I had just one mystery snail in my tank and she played eggs at the top then I hatched those babies in a different tank. But in the mean time I found a really pretty purple shelled and ivory bodied snail at the store and added it to the tank not knowing if it was male or female. Now my big girl who later eggs has been acting weird and sits there half open and doesn't move unless you move her and from the looks of if she now has a penis sheath? Do mystery snails change gender? I didn't think they did but I have been wrong or misinformed before. Thank you in advance

 

[MysteryShrimp]

Ok anyone who see this can disregard. I figured out that the little one I got is a male and I'm assuming the flab I see it a tunnel to the female organ since they are now doing their thing if you know what I mean.