I was freaking out too when I first got my BP because I noticed her neck skin getting super loose. Then after a few days she shed and everything tightened back up.
As far as the skin staying loose AFTER shedding, that could be a sign of dehydration/nutrition issues, but not for sure. She could just have loose skin.
As far as the stuck shed, I don't think stuck shed would cause extra wrinkles and folds.