Don't panic. You need to be patient and see what your smile is like in a few weeks. I understand it's hard though because it's an emotional time for you.
When they do lefort surgery most surgeons cut directly through the muscles above your lip, and those muscles are what control your smile. Once they have been cut they will need time to heal. Once they heal you'll regain more animation to your face. I haven't had surgery myself yet, but not being able to smile fully seems like a really common recovery complaint from people on jaw forums, and takes time to get it back.
2mm up, 2mm down - doesn't sound like you'd be at risk of over impaction. But you would need to know the final movements.
Regarding bottom teeth, it could be that your lips are swollen and covering teeth, or maybe it's to do with a genio. Again, it's way too early to tell because you're obviously still swollen. What were your planned movements for eveything?