I think you are worrying too much about your guppies. They will breed really well and multiply like rabbits without human intervention. I dont mean you shouldn't worry about their health, but things like whether she got any guppies left inside her and stuff like that.
The guppies are programmed to give birth to a lot with assumption that some won't survive because other fish, other guppies, and their own mother will eat them if they get in the way.
Just make sure you cretated some sort of rock formation or a plant for the guppy fry to hide in from the adults and everything will be ok.