Sad Dog

Question
I have a dog who is the baby of the family. We got her when she was a puppy, she is now 2 years old. She is very loving and craves attention, which she gets. Last night she started acting a little weird though. When my husband and I went to bed, she got really upset that we wouldn't let her sleep with us (she is allowed every so often). She sat outside our door and whined all night (she has never done that before). She also found a toy that she has become very attached too. Since last night, she has not let the toy out of her site. She is carrying it with her everywhere. She also seems to just be really upset about something. She has continued to whine all day today-to the point where she is shaking. The only time she is calm is if we are right beside her or giving her attention. She really doesn't seem to be sick-just...upset. If we leave the room, she follows us, whining until we come back and sit down. Then she will either lay on our feet or on our lap. I don't know what to do. We have tried playing with her, giving her pep talks, cuddling with her. Nothing is seeming to break her of this. Do you know what may be causing her to act like this? It's breaking my heart :(
If you need any other information: She is female, Pit Bull, not fixed, about 40 pounds. Never abused or mistreated.  

Answer
Hi Sarah;
I wopuld get her to her Vet as soon as possible.
The shaking makes me feel there is more likely something wrong, and they can't tell us if they are hurting or feel a little sick.
Rule out any medical reason first.
Of course there is always the possibility that she is just on a pity partuy, and trying to get extra attention, but it sounds like she is needing more of something.
If she has a toothache, headache, sinuses plugged up, or a number of things.
A low grade fever, from a little stomach bug or the start of a kidney infection.
There are so many things that would cause thes, and not necessarily be hurting her enogh to make her cry out.
The off and on sleeping with you could be confucing to her.
Does she have a bed of her own she can go to?
Charlotte