You will most likely lose these worries and be even more worried about your baby being healthy! I was worried about stuff like this too especially stretch marks which I did end up getting :( but you get to the point that you stop caring about your body and focus more on making that baby healthy and strong. Your body you can always take care of later don't stress over it, just sharing my thoughts sorry not the answer you needed. But good luck with everything(:
Your vagina goes back. And your boobs just depends on how much elastin is in your skins composition.
I'm sure you will have to be well down the road vet mom to have those worries lol
Your vagina will not be loose. It will go back to the way it was. Women's bodies are magical. Lol as for the boobs, I can't tell ya.