You have already gotten lots of good help but I wanted to add my advice
Tobie does both of these too but he has gotten soooo much better so I think the biggest part of it his her age. Tobie would whine so loud and so much if I just went to the bathroom and now he may whine a little bit if I leave the room for quite a long time but it's not bad at all. With Tobie I just make sure that I don't come to him everyone he cries. If you know that they aren't hurt or hungry or need to potty then it's best to just let them cry. When she stops crying then go to her and give her lots of praise and attention.
As far as the biting, I make sure to pet Tobie quite a bit and if he starts trying to bite at my hand I stop, take my hand away and say "no bite!". I wait a few seconds and then start petting him again. Usually after three or four times he gets it and will start licking my hand instead.
I just wanted to let you know what is working for me since I am going through the same thing. I think you'll be amazed at how much better she gets just within a few weeks time
